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§ Altirra 1.5 released

I actually released this last month, but for those of you still into Atari 8-bit systems, Altirra 1.5 is out. Once again, this contains a number of fixes to low-level emulation to closer match the actual hardware, and also contains some feature improvements such as more disk support and better input and UI options. The main page contains the full changelist for those interested.

An item that's somewhat hidden in the changelist is emulation of Video Board XE, which is an add-on board produced recently by some folks in Poland. It's FPGA-based and adds display abilities that are something like Amiga's bitmap capabilities combined with NES-style tile maps, while still being driven by an Atari 800XL or equivalent. While it is somewhat whimsical to extend '80s technology with 2010 video circuitry, I found the design interesting enough to hack in emulation for it so I could check out a few of the existing demos and also program it a bit. Long story short, I managed to get everything working well enough that I was able to write a program to do rotation via three shears on the blitter and it worked the first time on real hardware even though I'd only been able to test it on the emulator myself. It's a bit weird trying to write software to nothing but a spec, and rather gratifying when it actually works.

One of the problems I've run into when reverse engineering the Atari is that my hardware skills and equipment aren't always up to snuff. I'm primarily a software guy, and that limits my ability when it comes to reading schematics and determining what the hardware is doing, particularly when it comes to non-program visible results like color output. In the case of V1.5, one of the things I had to look at was emulating a particular bug in the chip that drives frame timing (ANTIC) which affected vertical blank. Unfortunately, the Atari's video output is borderline with regard to NTSC compliance; only one of the two capture cards I use can capture it at all, and the other one isn't configurable enough. Since I don't have an oscilloscope or logic analyzer what I ended up doing was hooking up the video to my sound card and digitizing at the highest frequency I could, 96KHz, which provided a barely adequate 6.5 samples per scan line. This was clumsy, but just enough to see what was going on with the vertical sync region and to emulate the bug. In doing so I learned tha modern LCD-based TVs frequently don't actually handle non-interlaced video correctly; they just pretend that the video is interlaced anyway. I suppose TV manufacturers aren't overly concerned with what the output from a computer in the early 80s looks like on a 46" HD display.


Comments posted:


I'm currently writing a Gamebase GEMUS script to start games with Altirra from the Gamebase frontend.
When writing this script, I ran into a problem, which seems to be a bug in Altirra (please correct me if I'm wrong).
The problem is with the command line options /kernel and /memsize.
Whatever I specify for these switches, I always get an error message
Command line error: Invalid kernel mode"
or Command line error: Invalid memory mode"
Example: Altirra /memsize:48K should work according to the /? screen, but I get the error message above.

There also seems to be a switch /hardware: (found in the source code), which isn't documented in the /? screen.

K.C. - 14 02 10 - 23:16

Don't know what happened, but yeah, the command line switching handling is fubared in 1.5. This version has a fix, along with some new switches added:

Warning: This build also contains some emulation accuracy fixes to STIMER timing which unfortunately slow down the emulator a bit. Need to figure out how to reduce the number of POKEY events.

Phaeron - 15 02 10 - 10:01

Moved from other blog..

Re Aztec error, just incase you didn't have the file..

Start the game and you will see the bouncing text, I'm sure that's not right..

Mclane - 15 02 10 - 20:40

Mclane, this is probably the only game in which you can see the error in the remaining games of explicit, visible errors are observed. :)

I'm still waiting for add *. bas files and normal save state.

breaker - 15 02 10 - 21:10

Ha ha Breaker, the fact the error happens in one game is not the issue, the fact that it happens could point to an emulation issue. If the same does not happen on real hardware then there's a reason and it can only help the emulation :)

There are loads of silly things I'd like, silly things like size and position remembered BUT I know the core of the emulator is what counts, without a solid core all the fancy bits mean nothing. Avery has surpassed Atari800win in my opinion and this emulator has numerous 'firsts' for Atari 8 bit emulation.

1st with SIO noise
1st with Vbxe emulation
1st with proper profiling and labelling (wip)
1st with Ultra tight drive speed and usage controls

And under the hood I suspect there are other firsts in the quality of emulation of the system...

So Avery, stop messing about and lets see a proper emulator :)

(NOTE! English sarcasm!!)

Mclane - 15 02 10 - 22:20

Sorry Mark, elderly moment..

I'll sort out the Bas thing but do me a favour, send me and email to remind me to as I lost my email contacts...

Mclane - 16 02 10 - 00:16

Mclane, I am aware of all this.
I reviewed a lot of games and programs, almost all works perfectly.
is true, some inaccuracies (such as a few broken on altirra cartridges), but otherwise just fine.

I am also well aware that the finalization of the emulator to 100% accuracy will only benefit.
but ...
most emulators first made basic things.
such things as:

- Save and load the file.
- Support all file formats.
- Settings for full screen mode.
and only then bring the emulator to perfection.

Phaeron, please do not be offended, I just expressed my opinion.
yours truly the best emulator of emulators atari 8 bit and I'm happy with any new changes, but you do it a little strange.

breaker - 16 02 10 - 02:39

Breaker, at this point, you're repeating yourself beyond the point of usefulness.

Mclane, the Aztec problem is an issue with mid-screen playfield width changes (DMACTL, to be specific). I've confirmed that the game runs OK on a real Atari, but I'll have to do some reverse engineering to figure out enough to emulate it properly.

Phaeron - 16 02 10 - 17:31

Cheers for the reply Phaeron, best of luck with that..

Mclane - 16 02 10 - 23:18

"In doing so I learned tha modern LCD-based TVs frequently don't actually handle non-interlaced video correctly; they just pretend that the video is interlaced anyway. I suppose TV manufacturers aren't overly concerned with what the output from a computer in the early 80s looks like on a 46" HD display."

Doesn't the wii still use non-interlaced mode for most Virtual Console titles?

Andrew Dunstan - 17 02 10 - 22:05

It very well might; I don't have a Wii. The Atari's video signal is also a bit out of spec, so that probably contributes a bit, too.

Phaeron - 18 02 10 - 15:38

If only the Atari hardware people had invented the PC and the Amiga OS people had supplied their OS to the PC..Would be a Perfect machine.

Mclane - 18 02 10 - 21:15

Alright, fixing the DMACTL issue was a lot nastier than I expected, but this version should fix it:

Phaeron - 20 02 10 - 15:34

thanks, phaeron.
error in the game Aztec challenge fixed.

that plan to do next?

breaker - 20 02 10 - 18:44

Thanks for the fix, would that error have affected other games in some way or was it a freak?

Mclane - 20 02 10 - 21:41

And a huge thank you for the screen size and location....A virtual beer / glass of Chardonnay heads your way!

Mclane - 20 02 10 - 22:09

Totally daft question now, the emulator name Altirra, is it based on that Manga Captain Altirra or does it have some other meaning?

Mclane - 20 02 10 - 22:38

Ahora grabacion CAS. Disculpa por molestar tanto. XD
Buen trabajo. Saludos

nsonic - 21 02 10 - 01:24

Now recording CAS. Sorry to bother much. XD
Good work. Greetings

nsonic - 21 02 10 - 01:24

Come on guys, stop asking for the same stuff time after time...Phaeron HAS heard you and answered already. Getting on his nerves won't help matters.

We get what we get and are happy about it

My opinion is that if you can't wait to see what Phaeron does then write the code yourself and pass it on to him to include, if you can't do that then just wait and see.

Things like the screen position were asked for right at the start, he didn't forget about that request and I suspect he will always looks at all possible requests and do what can be done if it's at all possible.

Mclane - 21 02 10 - 03:41

> Totally daft question now, the emulator name Altirra, is it based on that Manga Captain Altirra or does it have some other meaning?

Nope, but you are on the right track.

> Thanks for the fix, would that error have affected other games in some way or was it a freak?

It did affect other programs: Turmoil, Pacem in Terris, and Kasiarz. Kaziarz wasn't much of a problem, but getting Aztec and the other two to work at the same time was troublesome. It took me about three days of testing on the 800XL to figure out what the hardware was doing. The cycle timing is still not correct, but it's good enough now for all four programs to work.

Phaeron - 21 02 10 - 09:42

Cheers for the hard work and the name mystery will continue :)

Mclane - 21 02 10 - 22:39

Test version I posted to potentially address some sound issues reported by a user... posting for you folks too:

Phaeron - 22 02 10 - 18:42

but for some reason, it seems to me that the music began to play a little slower.
or am I mistaken?
well, more than any difference noticed.

breaker - 22 02 10 - 20:31

Music sounds better with the latest beta, as described it had sour odd notes, now much more tuneful. Does not sound slower to me but I'm musically deaf :)

I think it's maybe because the 1st tune already sounds unnaturally slow..

I could be wrong

Mclane - 22 02 10 - 21:40

with the new configuration has better quality sound and loud.
thanks for this update, phaeron.

and when will be made sound recording in wav?

breaker - 23 02 10 - 00:51

phaeron, I want to draw your attention to a small mistake in the game Oils well.
from the fifth level of play at the top of the screen appears jumping line.
in the emulator atari800winplus 4.0 this is no mistake.
I attach a screenshot of the game, place errors highlighted in yellow oval.

breaker - 23 02 10 - 02:37

The only reason I noticed the problem with the 1st demo is that in Altirra 1.5, the IRQ handler's timing happens to form a solid bar on the side of the screen. That doesn't happen on a real Atari, or in Altirra 1.6.

You could have mentioned that this was level *five*! I had to hack the game to get to that point.

It turns out that this is a bug in Atari800WinPlus 4.0. I tried the game on a real Atari 130XE, and it actually does have a glitch at that point. It's caused by a DLI handler taking too long before changing playfield color 3.

(Update: Oops, you did mention it was level five. Shows you how well I read....)

Phaeron - 23 02 10 - 17:29

Phaeron, as it stands now, how close do you think the emulation of the various chips and sub systems is compared to a real unmodded Atari.

It must be pretty close?

It seems to play anything that's thrown at it now that would play on a real machine or do you have a secret list of games that have problems still?

If I were you I'd be damn proud of what I have created so far...

Mclane - 23 02 10 - 20:27

How close? Well, probably about:

CPU: 95% (6502), 70% (65C02/65C816)
- BRK bug and some of the more unstable undocumented instructions not implemented, IRQ/NMI timing may not be exactly correct under some corner cases (particularly flipping the I bit exactly when an interrupt asserts or deasserts). NMI masking is not implemented.
- 65C816 mode doesn't use the correct bank in some cases. I think abs,X and abs,Y modes don't roll over, and a few instructions are using the data bank when they should be using the program bank. But then again, the 65C816 wasn't ever standard hardware....

MMU: 95%
- I believe that basic XL/XE support is fully correct at this point, but people keep finding ways to break the expansions -- partly because there are many variations of them for the same memory size.

PIA: 60%
- Banking and joystick ports are implemented, as are input/output port interactions, but there are a bunch of seldom-used features in the PIA that aren't implemented. These include interrupt modes and some of the odder output modes. The interrupt one is the troublesome one as it is program visible (you can force an IRQ into the 6502 through the PIA). Every once in a while someone comes up with a creative way to abuse the PIA chip that I don't support yet, like using it to play audio through the cassette deck motor control line.

ANTIC: 90%
- Everything is implemented, and as far as I know all DMA is cycle exact. The main problems come from flipping registers at odd places in the scan line. There are some known cases where the display of internal buffered data with playfield DMA disabled isn't the same under Altirra as on the hardware. I had to do a bunch of fixes here lately.

GTIA: 95%
- Haven't seen an issue here in a long time. Mid-screen changes are cycle exact in most cases. There are some weird glitches you can get by changing GTIA modes mid-scanline that aren't implemented, and switching sprite sizes in the middle of the sprite image has some anomalies on hardware that I haven't replicated.

POKEY: 85%
- This one I have the least confidence on in terms of cycle precision, although I think it's better in recent versions. There are also a lot of nasty analog effects on the audio output path that are hard to emulate, and unlike analog video effects, they're more important here. Historically, POKEY has been the least well emulated chip of all on the popular emulators, due to the difficulty of doing so efficiently and that it simply isn't that well known compared to the rest. There's an increasing number of demos that do not run correctly on many emulators because they require better than scan line precision on either the audio path or timer IRQs. Additionally, the pot timers aren't 100% correct, and I haven't bothered implementing light pen support yet.

Parallel Bus Interface (PBI): 0%
- Technically part of the XL, but very poorly documented on the software side and I know of no PBI device that anyone actually cares about....

Disk: 50%
- I think 810 level support is pretty good here, as I can boot just about all of the available VAPI images at this point. However, there are a whole slew of enhanced drive commands that I don't support at all, such as the high/ultra speed command set.

A lot of these issues are theoretical in that a high proportion of software already just works. The answer is no, I don't have a secret list of non-functional games or programs, as I think I've gotten through the backlog. Of course, every once in a while someone dumps a list on me and I have to get to work. The ultimate goal is of course to make it impossible for a program to distinguish between Altirra with enhancement patches off and a real Atari. So far, I'm pretty far from that as I have an entire directory of homebrew test programs I can use to break any current Atari emulator. The more realistic goal is to correctly run all known software, and Altirra is much closer to that -- it's pretty seldom that I can grab an Atari program and it doesn't run, assuming it isn't something obvious like the program depends on hardware I don't support. I suppose a third goal you could add is making it more appealing to use Altirra than a real Atari... which isn't hard to satisfy in my case. I recently did some Atari coding on an plane flight, which you can't really do with the real hardware.

What this all comes down to, fortunately or unfortunately depending on how you look at it, is that Altirra is reaching the point that VirtualDub is at, where it's starting to do a lot more than I actually need myself. Altirra is still a nimbler project, which is why I've been spending relatively too much time with it lately... but it's starting to show signs of becoming equally heavy development-wise. Formerly a lot of features weren't implemented and I could just knock them out one by one, but now it's at the point where I'm going pretty far into uncharted territory. Tracking down and nailing the DMACTL issues took three whole days. I'm also starting to get more attention because Atari800WinPlus development is dead, and no one has taken up retargeting the Windows UI to the latest Atari800 version -- flattering, but it can also be a bit overwhelming. It's a curse I bring upon myself by writing everything myself, I suppose.

I'll end with my saying that Altirra wouldn't have gotten nearly as far as it has without support. That includes you, breaker, everyone on AtariAge, etc.

Phaeron - 24 02 10 - 19:44

Thank you for you honesty Phaeron, as you will know by now I'm not on here to offer false modesty or attempt to bloat an ego, I truly believe in the emulator and appreciate the constant hard and often annoying work you put into it. Being slightly older than most I'd guess I can see it from the life POV, it's too easy to just imagine you get up and start coding Altirra every day and that's your whole life, people tend to forget that we all have more to do in life than just one thing and work can tend to totally destroy a lot of your free pleasure time. I'm 48, I have a 10yr old daughter and a lovely wife but I through one thing or another don't get the quality time I'd love to have, life gets in the way.

As for the quality of emulation, I would never expect you to achieve anything more than running what would work on a totally non modded, non 3rd party add on free machine to the best of it's ability. Supporting an 810 is more than enough, maybe standard 1050 support but no Happy drive, Lazer drive (a happy drive clone), archiver or other 3rd party stuff. Those are pure eye candy.

I'd love to just see you refine what you can as and when, in your own time, I hope others would understand that when something becomes a chore it's very hard to want to invest time in it so they should sit back and wait for what comes.

Cheers for THE best Atari 8bit emulator out there, long may it proper (jesus, I sound like a Trekkie!!)

Mclane - 24 02 10 - 21:26

phaeron, thanks for the detailed account of the work has been done, and for such a great emulator.
but even more we want to thank you for not abandoning this project and find the strength to continue work on the emulator and listen to our silly wishes;)

simply amazing how you manage so quickly develop an emulator, passed after more than a year since the first release, and the result ...
little more and atari800winplus left behind.

continue to work, I'll be glad to any change, although sometimes you want more.

breaker - 25 02 10 - 20:22

phaeron, thanks for the update.
sound has become more qualitative.
what makes the option view -> overscan mode -> Extended pal height?

breaker - 28 02 10 - 01:56

GTIA: Added option for displaying full PAL height when extending display past scan line 239.

Mclane - 28 02 10 - 02:52

in the game panther with the option view -> overscan mode -> Extended pal height, jerking the lower part of the screen.

breaker - 28 02 10 - 03:21

more errors

Debugger: Memory:
mouse right click / toggle write breakpoint / sets breakpoing on lower 8bits of address
must set on 16

breaker - 28 02 10 - 17:21

Pass, as it could be WIP we need to have a word from Phaeron on these..

Mclane - 28 02 10 - 18:46

I'm guessing the extended height may be a VBXE thing...

Mclane - 28 02 10 - 20:22

Good catch on the debugger bug.

Extended PAL height isn't related to VBXE. Normally, ANTIC only allows you to display 240 scan lines even in PAL, where you have almost 100 more scan lines available. It turns out that there is a bug in ANTIC that can be exploited in order to generate a full height PAL display. This is hard to take advantage of because you can only use sprites, but you can do it. I added this at the request of someone who was experimenting with such a display. The bug in this case is that the emulator should be blanking out the extra height regions when the bug isn't active.

Phaeron - 01 03 10 - 15:48

phaeron, I just now noticed.
when you open the cartridge specified file types *. BIN and *. ROM, and cartridges with the extension *. CAR not specified.
Fix it.

I also want to ask whether the added tuning frequency sound from 8000 to 48000 Hz?

breaker - 01 03 10 - 17:40

> I also want to ask whether the added tuning frequency sound from 8000 to 48000 Hz?


Phaeron - 01 03 10 - 18:03

sound quality.
sampling rate.
in the emulator atari800winplus, from 8000 to 48000 Hz.

breaker - 01 03 10 - 18:22

I hope the author who is working on the program using the extended height is going to point out this for Altirra as I leave it turned off as it plays havoc with other games etc..

@Breaker, fix it is normally expressed "could you fix it please". Your translated fix it comes across as a bit rude.

Mclane - 01 03 10 - 19:49

i`m sorry

breaker - 01 03 10 - 20:33

No problem, just helping where your translator may be failing

Mclane - 01 03 10 - 23:06

New beta

Sparky - 07 03 10 - 21:53

Sparky, we know about it.
not do more so, this beta is not laid out as it is not finished.
I do not spread hidden beta.

... but I see everything;)

breaker - 08 03 10 - 01:00

As breaker says we don't know how finished the beta is as Phaeron has not announced it as far as we know. I've been using it without fault so far so it's probably fine but we just don't know :)

Mclane - 08 03 10 - 01:31

Breaker, the created date is different from when we first saw it, oddly it's older?

Seems odd?

Mclane - 08 03 10 - 04:53

Mclane, I checked the file in exactly the same, no differences.
waiting for new build from phaeron.

breaker - 08 03 10 - 15:09

Shouldn't have changed... I didn't upload another beta. Let's change that:

Mostly changes to the debugger, particularly for 65C816 mode, so not much new user-side... but one change that may affect you is that I fixed a bug in the SIO emulation. Specifically, the Total Daze demo should now load more reliably; it used to occasionally hang if accurate sector timing was enabled.

Phaeron - 08 03 10 - 16:27

I have a couple ataris, an 800 with the memory bank switching circuit, and a 'newer' XE, for anyone interested.

jeves - 08 03 10 - 17:12

Jeves, where are you?

Mclane - 08 03 10 - 19:58

>UI: Added .car extension to Open Image dialog.

you forgot to add support for that file type.
this must be done and for the Boot image

breaker - 08 03 10 - 20:03

Thanks for the new beta Phaeron, there's nothing like the smell of a freshly cooked Altirra to perk you up :)

If memory serves me rightly the 65C816 is the processor used in the Snes, love that system and cheating games was such fun.

Mclane - 08 03 10 - 20:05

Breaker, could you not just rename the .crt's to .roms which is what they are in essence.

Mclane - 09 03 10 - 01:01

Phaeron, Mclane, beg you check the sound of music on a real atari and emulator altirra.
I for some reason, it seems that the music sounds a bit slower than it should be.
using pal emulation
listening to music from the game Panther.

breaker - 09 03 10 - 17:11

Sorry Breaker, can't help you there as I don't have real hardware any more..

From memory of the things I have played in real Atari's the sound of the music and speed is right but as we know the pokey emulation is the hardest of all. You could well be right as you do have a good ear for sound as noticed already.

Sadly unless we can provide Phaeron with three things he can't do much more than the excellent quality it already is.

The three things are:

1. a large amount of free time he's willing to use

2. An Oscilloscope

3. And a logic analyser for good measure..

With that and an awful lot of very boring hard work he could perfect the sound and other parts of the emulation bring most things near cycle exact.

I think that's a bit much to ask though :)

Mclane - 09 03 10 - 19:29

Just wanted to add that the A800 team are working hard on the pokey emulation, I'm sure they have learned from Phaerons work so if they do make some form of breakthrough I'm sure Phaeron could pick up some pointers if he needed them.

Obviously I'm not suggesting code theft or breaking any coding / usage rules.

Mclane - 09 03 10 - 19:33

I'm not exactly sure, but ..
I listen to music on the player asap, and then listened to the same thing on an emulator, it seemed to me that the emulator sound a bit slower.

breaker - 09 03 10 - 19:36

ASAP is itself an emulator, just one that only emulates POKEY and the 6502. In order to check, you'd need a real PAL Atari. That having been said, I ran both ASAP-Flash and Altirra at the same time and they were basically playing in sync for a long time.

One thing to keep in mind is that Altirra has the additional constraint of keeping audio and video in sync, so if the video glitches it can force a slight correction in the audio timing. Since PAL Ataris run at 49.86Hz and most PCs run at 60Hz or 72Hz refresh, this is actually fairly likely to happen once in a while. If the playback rate is a bit unstable, you may have slightly better luck if you disable vsync. Raw audio recordings, however, are uncorrected and are always produced at exactly CLK/28 rate.

Speed issues in games like Panther actually don't generally require the uber-detective work, because their timing is very simple: they're based off of VBLANK. This is extremely reliable and hard to get wrong in an emulator if you want to even get to the OS boot screen. The nasty ones are digisounds or other very high frequency tricks, which aren't used in games much because they don't leave much CPU time for anything fun to play.

The Atari800 team has the unenviable task of trying to improve audio quality while still supporting some fairly low CPU power platforms... it's a lot easier to emulate POKEY precisely when you can afford cycle-level emulation and a brute force FIR low-pass filter. I'm curious to see what the next release after 2.1.0 will be like.

Phaeron - 09 03 10 - 20:29

thanks for the explanation Phaeron.
few questions:

1) Will you add playback rate from 8000 to 48000 Hz?
2) Can you add to the emulator support files *. sap?

breaker - 09 03 10 - 21:19

Why and why?

Mclane - 09 03 10 - 21:55

why not?
I would like to see this emulator as the best atari emulator in the world.

breaker - 09 03 10 - 23:26


cassete not runs in my own code, after i set #$34 to PACTL, PBCTL

There should be a loading cassette through a turbo-loader.
The loader I spread.
I spread a turbo of record of cassette earlier.

breaker - 10 03 10 - 02:48

I don't understand the concern for 8000, 99% of emulators use 32000, 44100 and 48000, any lower seems pointless.

As for a SAP player, well it already is one if you think about it, bolting on a SAP player just seems eye candy?

As for the loaders, iirc Phaeron has said it does not cover all the baud rates so far but I could be wrong here..

Mclane - 10 03 10 - 03:55

it just should provide SKSTAT (bit 4) register any time, and should play tape when motor ON

breaker - 10 03 10 - 16:58

Pass, I pass to your superior knowledge, I never played with tape loaders, just disk routines.

Mclane - 10 03 10 - 20:25

while we wait for a new build of the emulator, I want to introduce you to my level for the construction of the best games for atari: Boulder dash Construction kit.


first start the game Boulder dash Construction kit.
from the game menu, select to play (figure 2).
open the disc levels.
after the title, enter the code (file name).

I have done and debugged these levels more than 2 years old, seeking a perfect balance.
all levels of the game are traversed, verified!

breaker - 14 03 10 - 19:56

phaeron, I found a bug in the emulator.
used the game Boulder dash construction kit.
I created a new, blank disk and tried to format it, but I have not got.
receive the message check your drive.
set the drive mode R / W or virt R / W does not help.
emulator can not write files to disc?

in the emulator atari800winplus 4.0 recorded on the disc works.

breaker - 14 03 10 - 21:16

Did you run an .atr or .xex version? I got the same error you did when running the .xex on either emulator, but the .atr works fine. My guess is that the operation fails because DOS hasn't been loaded.

Phaeron - 15 03 10 - 15:47

I used a version of the game on the ATR.
found another bug in the emulator:
If during the game to enable or disable stereo, appear error.
for example in game boulder dash disappears sound, game alley cat after you start hangs, and the game, panther, begins to play in a circle.

breaker - 16 03 10 - 03:09

I would not call that a bug, you are altering the emulated hardware mid way, it's bound to cause an issue with a lot of programs. That's why you can't just switch processors with a reboot taking place.

I personally just took it for granted that I either switched to stereo and then booted in a game or switched to stereo mid game and rebooted it. And obviously vice versa..

Mclane - 16 03 10 - 05:10

Hi Phaeron, just a little idea I'd like to run past you if I may..

I was trying to help out Mark who does the excellent Atari Gamebase, I converted a load of .bas files into atr's so they could be booted by the emulator. He then asked me if I could help on .cas images ie the CLOAD basic ones which I can't as they require human typing which I can't automate.

I've looked at the headers of basic and non basic .cas files and the cload ones have a unique header (well the ones I looked at did). Would it be possible to automate their loading so that anyone who's not savy could just boot them up.

Possibly an internal automated typing of the cload followed by the two presses of the return and the run once loaded.

Would this be something you might be interested in doing or is it far too much work and headache?

Obviously it's purely an idea, if its wacko then joke poke me in the eye with a sharp stick :)

Mclane - 16 03 10 - 21:31

I'll wait for Phaeron add support for *. bas files in the emulator.
cassettes because like, and so are automatically loaded through the File ---> Boot image

breaker - 16 03 10 - 23:15

phaeron, Mclane, a little stupid question:)
Prompt how to write down please on an empty disk levels from game Boulder dash construction kit?
If it is possible describe step by step this process.
I did it last time five years ago and now I suffer I can not recollect in any way.
I very much wish to do new caves again.

breaker - 16 03 10 - 23:44

Breaker, most cassettes are booted that way but Basic ones need to be loaded manually

Mclane - 17 03 10 - 01:35


Grab this

make a disk under Altirra, boot up DOS 2.5, format the disk, load up that Boulder dash, once into the editor go to disk drives, swap the boulderdash for your freshly formatted new atr making sure the protect mode is set to R/W. Hit M on the key board mand make sure it saves..

Mclane - 17 03 10 - 04:54

thnxx for the great work new emu for the great and the best homecomputer :) 8 bit rules.
i am still a great fan :)

marcokitt2000 - 17 03 10 - 07:37

I do not understand, can not I format the drive.

what I did:
1) created the disk
file ---> disk drives, new.
chose 256 bytes (DD)
uploaded Dos II 2.5 (v1). atr
put the second drive, a blank disc in the properties of the second drive said R / W.
pressed I, said the drive number 2.
in dos receive the message "Error - 143"
if you disable sio patch receive the message "Error - 138"

trying to reformat the drive in the game, receive the message "Check your drive"
what am I doing wrong?

breaker - 17 03 10 - 18:21

Either I'm going mad or there's something wrong....

It's like it can't format a DD drive, single density works perfectly???

I've tried various DOS's and made atr's with both Altirra and AtrUtil.....Altirra recognises the DD disk if premade but refuses to write to it??

Mclane - 17 03 10 - 21:26

ha ha ...
Mclane, you're right ...
altirra allows you to record and formatting of SD disks (single density).
but refuses to format and write to disks DD and above.

strange bug.

breaker - 17 03 10 - 22:21

Many emulators (WinUAE, MAME, Fusion [Sega Genesis], ZXSpin [Spectrum/Timex]) has got the ability to overlay png masks on a DirectX surface to simulate the CRT TV/RGB monitor/VGA monitor display. Will something like that be possible in Altirra?

WinUAE screenshot w/ vertical aperture grill png overlay - [1,5MB image]
WinUAE screenshot w/ scalines png overlay -
(ther is also tv noise, bluriness, artifacting etc. visible on the screens - so-called "PAL filter" from WinUAE & VICE emulators)

galu - 18 03 10 - 01:30

galu, may later be added filters, but not now.
phaeron makes emulator as accurate and qualitative, which will be sufficiently emulated all the details atari then perhaps will other things.

breaker - 18 03 10 - 02:34

Hmmm..The only effect I have ever used on emulators was the 3D screen warping on Final Burn Alpha, it gave that arcade feeling. As for emulators like WinUAE & Altirra the only thing I use on them is Bilnear filtering.

I could be wrong but I seem to remember Phaeron saying that the Virtualdub shell that altirra uses isn't suited for those sort of overlays. Could be wrong tho...

But as Breaker rightly says, Phaeron is mostly working of emulation quality although he has been known to suddenly work on something totally unrelated :)

Mclane - 18 03 10 - 05:40

About the display, Mclane is correct: Altirra's display system is based on VirtualDub's, which is geared toward high speed display of video. It doesn't have the ability to handle arbitrary rendering or a composition tree, thus the reason for the limitations. I've been considering adding such capabilities so that better status displays are possible, but things like aperture grill overlays I consider fluff that's lower priority than a lot of other things I could add.

The reason for the DD format failure is that Altirra only mainly emulates an 810 disk drive; double density disks will read if mounted, and I added the Read PERCOM Block command as a request, but it doesn't emulate all of the commands that a 1050 or XF551 drive supports. The two offending commands here are Format Medium Density and Write PERCOM Block. I'll have to look into implementing these at some poin t.

Phaeron - 18 03 10 - 17:53

Thanks for the explanation..

Any thoughts on the CLOAD idea either good or bad?

Mclane - 18 03 10 - 20:35

and the playback rate and not added.
and with a tape error is not corrected.

breaker - 18 03 10 - 22:49

There's a new beta out but mainly cpu fixes with Pokey tweaks

Mclane - 19 03 10 - 03:13

Phaeron, understand that you've fixed, but anyway thanks for Beta 10.

breaker - 20 03 10 - 16:06

FYI, test 10 just contains some fixes to the debugger.

Phaeron - 20 03 10 - 17:31

phaeron, I certainly understand that the accuracy of emulation is very important, but ...
whether we will see at least in version 1.7, such things as:

- Save states
- Support for *. bas files
- Record video and sound
- Support for the rest, not working into altirra, cartridges.


breaker - 20 03 10 - 17:46

Breaker, what is wrong with you?

Are you trying to sabotage Altirra by constantly asking the same questions despite being told by the author himself that it was verging on annoying. Do you know how many projects such as this have been dropped because of similar behaviour, I remember one where the guy was just getting message after message from AOL kids saying your emu sucks, when are you going to do x y z and why have you not done X Y Z...

He simply got so annoyed he dropped the project just so he could have peace..

If that's what you want they keep on going with the constant requests of where and when, maybe it's a nationality thing ie Eastern Europeans are more up front and direct with their requests maybe?

Personally that is frowned upon, once it's asked it's over and done.

This is not personal, you have contributed much to fixing stuff but I don't want to see Altirra dropped out of frustration, you really have to see that when Phaeron hits the wall as of he can't get the emulation more correct due to no documentation or no testing hardware to check with then I suspect only then will he start looking at the minor things like save states, other cart emulation and avi making.

It could be another 100 beta's or more but I'm just grateful he's giving it his best shot, he's got to pay the bills and have a private life...

Please, just keep pointing out the bugs and offering idea's and leave the requests that you know he has heard and replied to alone

Mclane - 21 03 10 - 04:11


Only change is that I cranked the high-pass filter on the audio path all the way down to address the warbling concerns. This will make the sound a bit bassier than it should be, but there are apparently undesirable interactions right now between the high-pass filter and the box filter I'm using to downsample from 1.79MHz.

Phaeron - 21 03 10 - 11:04

Mclane, I understand everything, but I want to see something real in the emulator.
phaeron, please do not be offended, but I got used to a good game in the emulator, you also are full of hardcore turns.
Project altirra - an interesting project, and perhaps it will be the best emulator atari, but apart from the super-accuracy in the emulator a lot of what is missing, especially convenience.

that's left to do in altirra to make it the ideal emulator:

1) save states
2) make 3 and 4 inputs for control.
3) additional control (Light gun, Light pen, trak-ball, Koala pad, etc)
4) settings are available from the Full-screen mode
5) File associations
6) Playback rate
7) record sound and video.
8) Search Cheat-Codes
9) deceleration and acceleration simulation
10) Support *. BAS files.
11) recorded on tape.
12) game on the network.
13) preservation of all setting the emulator to a separate file.

As you can see the work yet to do very much.
I am sure phaeron enough strength and patience to realize all this.

breaker - 21 03 10 - 16:13

That's a very long list. I assume you realize that if you repeat it every time I post a test release that it's going to get very, very tiresome?

Also, while I'm generally open to suggestions and to the items on this list, I'm going to warn you that I don't care about #6 -- I don't see any point in adding support for playing back audio at a uselessly low sampling rate. You're going to have to try harder than "other emulators have this" in order to justify why this is worth adding.

Phaeron - 21 03 10 - 16:41

well, it was just a list of which lack the emulator.
when you instantiate it is not so important, I'll wait a year and two years if necessary.
and I will continue to test and help you in any way.

but if you knew how embarrassing to play in the emulator without saving.

breaker - 21 03 10 - 17:06

Forgive me, more of this will not happen again.
I will continue to wait.

breaker - 21 03 10 - 17:36

I like the new filter settings, the added bassinest sounds right to me, Caverns of Mars has the proper boom when you crash.

Incorrect or not it sounds good...

Mclane - 21 03 10 - 23:10

why sometimes in the game Caverns of Mars sounds of squealing?

breaker - 22 03 10 - 02:26

What version and where Breaker?

Mclane - 22 03 10 - 03:14

I did get weird noises on Air Strike I & II at some points but I think it was the cracks and OS

Mclane - 22 03 10 - 03:19

detected an error.
the game Caverns Of Mars II (v2). atr, instead of the shots could be heard a pop.
in the emulator atari800winplus 4.0 in this version of the game the normal shots.

breaker - 22 03 10 - 17:05

thanks for test 12, Phaeron :)

breaker - 22 03 10 - 17:38

Adds support for formatting medium (dual) density disks and for XF551 high-speed mode, as well as binding an input map to a specific controller index. This allows you to set up more than one game controller.

The issue with Caverns of Mars II is one we've seen before, a game that doesn't reset the serial port mode properly. The funny part is that the pop is actually the correct sound -- that's what I got with the real 800XL. The squeaking that you get in Atari800 and in Altirra with the SIO patch on is actually the wrong sound, but that was probably the intended sound. I'm guessing this is a bad disk rip, because I can't imagine that the original APX disk would have been shipped this way. Maybe I'm wrong.

Phaeron - 22 03 10 - 17:50

phaeron, can you give even a system requirements for the emulator altirra?
A friend says that altirra brakes on his computer, there is a drop in FPS.

a computer for the emulator you're using?
I have: Intel Core 2 Duo E8400 3.6 Ghz, Nvidia GTX260, 4 Gb memory, Windows 7 x64 ultimate.

breaker - 22 03 10 - 18:02

About a 1GHz system is enough -- I've run it on a 1.6GHz Atom based netbook before. Yours is very overpowered.

If I had to take a guess, the most likely issue is a problem with the graphics card. Running with /ddraw or /gdi may help.

The current versions are a bit slower; the fastest I see is about 1600% NTSC (1000 fps) and it sometimes slows down to 500% (300 fps). This is due to the POKEY emulation, which is fairly expensive. I need to rewrite the POKEY module at some point.

Phaeron - 22 03 10 - 18:27

phaeron, you could add an option in the emulator Skip Frames?
it may very well speed up the emulator on slower computers.

Please do not take this as an annoying request, it will be just a really good improvement.
my friend's computer with a processor at 800 Mhz, he said altirra that gives only 20 - 25 fps.
skip frames - can improve.

breaker - 22 03 10 - 20:11

No one AFAIK has asked for frame skipping before so it's not an annoying request Breaker :)

Nice system by the way, puts my dual core P4 with Nvidia 7800 card to shame :), if you find another one please post it to me :)

As for Caverns of Mars, there's several rips so I would imagine there's a few bad ones in there as suspected.

As for your list of requests, as Phaeron has said he wants reason other than 'another emulator has them' so I'd like to make a comment on them, I'm not criticizing nor suggesting them, just giving my thoughts on them. Please don't use this as a way to re plug them Braker :)

>>1) save states

Yup, nice idea, dead handy all round. Would love to see them

>>2) make 3 and 4 inputs for control.

4, I think is too far, certainly Atari rethought that themselves hence only 2 after.

>>3) additional control (Light gun, Light pen, trak-ball, Koala pad, etc)

Hmm...Only Atari made peripherals I feel, track ball would be nice. We at Maplin made light pens for it but the coverage of them was little, I'd stick to tack ball and maybe touch tablet at most.

>>4) settings are available from the Full-screen mode

Yeah, different resolutions would be nice but at the mo mere eye candy..

>>5) File associations

Personally, this is something a user can do for themselves AND some will be over written by other emulators so a tad pointless.

>>6) Playback rate

As said before, I thought it was uneeded, most if not all emulators offer somewhere between 32000 to 48000, anything else is a waste..

>>7) record sound and video.

Not one for me, pure eye candy, one for Phaeron on a really bored day..

>>8) Search Cheat-Codes

Two minds on this one, would I like added commands to the debugger or a little cheating only interface, a cheat only interface is what I would go for as easier to comprehend to new users, lots of /t and /s debugger commands may look daunting. Certainly an option I'd like but again pure eye candy at the moment.

9) deceleration and acceleration simulation

Again, not one for me, I can see it's uses but it's really few and far between, filed under another one for Phaeron if he really is that bored.

10) Support *. BAS files.

I'd imagine the process for injecting this is more tricky than other idea's, there are way's around this that a user can manually do but there is a wish from many for this, for ease of use by a new user it would be nice as would maybe my CLOAD idea but accuracy comes first for me.

>>11) recorded on tape.

Pass, can't quite see the need for this other than for emulation completeness.

>>12) game on the network.

Never understood this 100%, I've spoken to many many Atari users and I swear I have never had anyone admit that they multiplay online. For me it's less important and does not come under emulation completeness as the Atari never had it as a feature.

>>13) preservation of all setting the emulator to a separate file.

The registry is fine, why redo an item that is working fine. That was a rhetorical question by the way.

Mclane - 22 03 10 - 22:22

Here's the problem with frame skipping: it's unlikely to help much.

Emulators are always split into two halves. One half is the core emulator which simulates the hardware; this part has to run in lock step for good compatibility. The other half is the front end, which handles transforming the emulated state into something the user can see and interact with. The front end is the only part you can safely add frame skipping to without affecting emulation quality. If you skip frames in the core, you start going down the bad path of making changes that are visible to the emulated program, and with an architecture as timing sensitive as the Atari 800, that's likely to cause a crash. In addition, a lot more functionality is in the core than you might think. For instance, you might think that the video display logic can be skipped, but it largely can't, because that logic is also involved in sprite collisions which can be detected by software. The only part that can be skipped is the very last part where the priority outputs are converted to colors.

The problem in Altirra's case is that the performance profile is heavily skewed towards the core. On my dev machine, running Alley Cat at 1x speed, over 90% of the CPU time is spent in the core and less than 10% in the front end. To put this in perspective, completely turning off the display on a machine that is running below 1x speed and has a 90/10% split will only cause the emulator to run 11% faster.

There are a few things your friend can try. First, try closing the display window and activating warp speed. That will show you the absolute best speed possible with frame skipping, since that's what warp speed does. Second, try disabling vsync and see if it helps, as that can slow down things on some systems with poor video drivers. Vsync off + warp on may give a workable boost if the display really is the bottleneck.

Phaeron - 23 03 10 - 15:19

well, thanks for the explanation.

breaker - 24 03 10 - 00:58

A Direct3d question for you Phaeron if I may, I have a P4 3.4gig 2 gig mem and a Nvidia 7800GTX video card, obviously that's an old card. If I was to upgrade to a newer card can I expect much difference, I can't go too mad as I only have a PSU with 1 mini graphics card adaptor and the PSU isn't meaty enough for a big expensive card (which) I can't afford anyway.

So would a middle of the range newer card offer me more ommph or amn I going to be bottlenecked by the CPU I have..

Mclane - 24 03 10 - 01:54

A 7800GTX is complete overkill for Altirra. To give you some idea, a video game might render several hundred polygons per frame. Altirra renders... two. You probably wouldn't have any problem with even a 6200 and maybe even a FX5500, much less anything in the 7xxx range. I get full speed with Intel Integrated Graphics, even.

The cards that can be problematic that were made before pixel shaders, such as a Radeon 7500 or a GeForce 2. The reason is that Altirra leverages pixel shaders in order to accelerate the conversion from Atari 8-bit colors to RGB; when this isn't available, the conversion has to be done in software and that requires 2-4 times as much graphics data to be uploaded per frame. The last generation of fixed-function only hardware is fine; prior to that, the problem becomes less of speed and whether it works at all, because in prior eras the graphics card manufacturers sometimes didn't even bother to check if some of the features they "implemented" actually worked.

Phaeron - 24 03 10 - 20:44

Thanks for the usual HQ reply, Altirra is spot on for me, my old 19" Dell / Sony monitor I had before sync'ed to 100Hz so Altirra was silky silky smooth, sadly that died and I'm stuck with a flickery 60Hz or 75Hz top which is more than fine. Emulation wisealmost every thing runs fine with the exception of Byuu's lovely Bsnes when running SFX or SA1 chipped games or MAME on the newer stuff. From what I can gather from you nad other the GFX card does have some input but most of it is down to software and CPU with my CPU being one of the older Pentium one sisn't as powerful as the newer dual or 4 cores.

MAME is an issue onto itself I know, dedicated emulators for some of the games run very much faster.

Mclane - 24 03 10 - 21:29

Nothing to do with Altirra and probably of no interest to anyone..

Don't you hate that jolt of life moving on and telling you how old and fickle you are?

Was just having my morning scan of websites I go to and spotted a headline on a comic site I enjoy, the legendary Dick Giordano had died aged 77. To most people that will mean nothing but if you were born in 63 like me and grew up with 70's American comics his name is legend. He and Neal Adams produced some ofthe most ground breaking and realistic comic art & stories there were in the very censored era of the time. Neals art and Dicks inks just fed the eyes a feast of art unlike what had been seen before.

So as I sit here heading towards 49 it was a stark reminder of just how old I am, things from my childhood just switching off like light bulbs never to turn back on.

Gloomy or what!

Mclane - 27 03 10 - 21:55

We all, only children, only large.

atari helps me go back a few minutes in childhood, in those same years.

breaker - 28 03 10 - 01:17

thanks for test 13, Phaeron :)

what`s new ?

breaker - 28 03 10 - 14:24

Whoops, uploaded that and forgot about it. Just one new option: you can now toggle memory randomization on power on. I added that because there are several games that rely on uninitialized memory and break if extended memory is scrambled, such as the Homesoft version of Run For The Money.

Phaeron - 28 03 10 - 15:07

Cheers Phaeron...

@breaker, yes what you say is soo true, when I'm fiddling with Altirra and the games I'm almost transported back into the time, I can almost feel the excitement of wandering into Silica Shop (a HUGE Atari dealer in the day) and seeing all that lovely hardware while hearing all the game sounds like Galaxian, Bounty Bob and Pac Man bleeping out of the show machines.

Almost heaven :)

Mclane - 28 03 10 - 21:53

Another update... SysInfo 2.21 is once again detecting Altirra as an emulator. This means war:

Phaeron - 29 03 10 - 16:48


Mclane - 29 03 10 - 18:51

ups !

breaker - 29 03 10 - 21:25

Ah, a possible bug...

Was just playing about getting Sysinfo 2.21 where I came about a bit of a problem..

If I make a disk under Altirra and then save it making it R/W I can then under Altirra run DOS and format it fine under standard Atari DOS. I can copy files to the disk and run them but If I shut ALtirra down and restart it and try and use that same disk again Altirra tells me it's corrupt or unrecognised yet if I load it under Atari800win it says the disk is fine and allows me to run stuff off of it..

Mclane - 29 03 10 - 21:31

Btw, I don't mean boot the disk, it just won't even let you mount it..

Mclane - 29 03 10 - 22:20

Breaker, see if you can replicate what I have done just incase it's me being an idiot?


Mclane - 30 03 10 - 20:20

Mclane, sorry, I can not help you.
I've never used DOS and have no skills for him.
I created a blank disk and format it under DOS 2.5 (v1) - it works.
how to copy files from one disk to another under DOS, I do not know.

I do not have real atari, but in those years when I used the atari 8bit about the drives we did not even know.

breaker - 30 03 10 - 22:08

Ah ok, you can still help me, Use Altirra to make the disk and format it then write dos files to it, make sure the disk is set to R/W. It should format and write dos files quite happily and boot the image you made.

Now quit Altirra, re run it and try and boot that disk you made and wrote DOS to, Altirra if it is an issue will say it's either unrecognised or corrupt.

If it does not then there's an issue my end..

Mclane - 30 03 10 - 23:38

Mclane, I did what you told me and got an error.
what I did:

1) loaded from the drive № 1 DOS 2.5 (v1). Atr
2) create a blank disk in the drive № 2 - DD 256
3) exhibited for the drive № 2 R/W, formatted disk.
4) all went well.
5) chose "H - Write DOS files", said drive № 2
6) all went well.
7) closed the emulator.
8) try to load this disk, emulator Atari800WinPlus opens the disc and on a blue screen I can see the inscription running down the "Boot Error".
9) try to open the disc in the emulator altirra, I get a message "Disk Image" new disk.atr "is corrupt or uses an unsupported format."

breaker - 31 03 10 - 00:34

Thanks Breaker...Perfect...At least I know it's not me...

That same disk will work happily on Atari800win..Seems a little disk creation / recognition bug had crept in. One for our Lord and Master Phearon to check up on whenever he has time..

Mclane - 31 03 10 - 00:55

always happy to help ;)

breaker - 31 03 10 - 01:40

I wish every one could have Girder

And Strokeit

And they were made to learn to how to use them, they turn your mouse into a lethal weapon, ok not lethal but really handy for controlling apps in any way you can.

Stokeit will allow a multitude of ways to make your mouse assign key presses etc and along with girder you can find the WM_COMMANDs for apps. No time for tutorials but if I can learn it then anyone can.

This thread taught me loads

Now I use right mouse button left to load a game, right mouse button right to reset the emulator, right mouse button up to set it to XL / XE PAL 320 ram and right mouse button down to set it to atari OSB 48K.

Mclane - 01 04 10 - 01:29

Found another issue, not sure if it's a bug or not...

I was sat down to have a bash at Astro Chase, for some reason it got to the title screen, then went a screen with the planets and score and the the character base was reset so the planet was just a jumble of characters.

I went through all my settings and found the cause, I had being playing about with the H: handler and pointed it to a directory on the HD.

Soon as I disabled the H: and rebooted the game it was fine.

IS this meant to be,sorry about passing on this and the disk error work :)

Mclane - 02 04 10 - 00:21

I've seen the disk image problem before but haven't gotten a chance to track it down yet. Been too busy.

The Astro Chase lockup issue appears to be either a bug or a deliberate anti-hacking mechanism. There is an explicit check in the program for a sixth CIO handler (HATABS+15) and it locks up in a loop if one is detected. The program doesn't use that byte for anything else.

Phaeron - 02 04 10 - 18:02

Thanks for taking a look, hopefully busy = earning money :)

Mclane - 02 04 10 - 20:16

Figured out what was happening with the disk issue:

The incremental disk flush code was only flushing the data and not the header, so if the format command had changed the disk format, the header didn't match.

Phaeron - 03 04 10 - 10:51

error remains uncorrected.
made the following steps:

1) loaded from the drive № 1 DOS 2.5 (v1). Atr
2) create a blank disk in the drive № 2 - DD 256
3) exhibited for the drive № 2 R / W, formatted disk.
4) all went well.
5) chose "H - Write DOS files", said drive № 2
6) all went well.
7) closed the emulator.
8) try to load this disk, emulator Atari800WinPlus opens the disc and on a blue screen I can see the inscription running down the "Boot Error".
9) try to open the disc in the emulator altirra, I get a message "Disk Image" new disk.atr "is corrupt or uses an unsupported format."

made the disk in the emulator atari800 winplus.
with the new disk, booted dos.

breaker - 03 04 10 - 15:44

more interesting.
Disk made in the emulator altirra not open in utilities.

AtrUtil Version 1.13 - gives an error "error opening file (Code 0).

try to open the disc utility makeATR v0.6.
error message "This is not ATR file. Cannot continue".

Disk created in the emulator atari800WinPlus 4.0 opens fine in both utilities.
disk visible DOS sys files and Dup sys.

breaker - 03 04 10 - 15:57

Have to say it works fine here now although it refused to boot / mount the disk made with beta 14.

Formatted both single and enhanced density with no issues after a reboot..

If I remember true double density isn't supported yet so didn't try that...


Mclane - 03 04 10 - 19:42

Is there a command line option for fullscreen ?

Krakerman - 10 04 10 - 19:00

Fraid not....Alt + ENTER are the only way in and out...

Mclane - 10 04 10 - 22:25

I do not understand why you need the command from the console, when there is a pressing alt + Enter.

vitrtual dub 1.9.9 came out, and I think that the new release altirra delayed.

breaker - 10 04 10 - 22:36

Who says there's a new release, Avery could be lying on a desert beach, havong a few coctails and enjoying a holiday :)

Mclane - 11 04 10 - 02:38

Because if you want to use a Frontend (ex. GameEx, Maximus Arcade)to run the emulator you want to run the game straight from that to full screen.

Krakerman - 11 04 10 - 05:38

Added /f for fullscreen:

This version also contains support for full NTSC artifacting. It works by doing the equivalent of synthesizing a 28MHz NTSC signal and then separating it back out into Y/C components, so it isn't as crisp as classic artifacting, but it's fairly authentic. The algorithm could still use a bit of tuning -- right now it ignores the color adjustment parameters -- but at least the speed is decent.

Phaeron - 11 04 10 - 10:23

Very nice :) Thanks for that fast update!! Works like a charm.

Krakerman - 11 04 10 - 11:12

thanks for test 17, Phaeron :)

what's new in the beta release of 17?
I understand you have not fixed the error writing to disk?
Tell me, you will add PAL artifacting (High)?

breaker - 11 04 10 - 16:02


Mclane - 11 04 10 - 18:29

Thank you, Mclane.
I realized, fixed error ANTIC, right?

breaker - 11 04 10 - 19:27

I do not know a bug or not, but decided to announce, just in case.

Game Dropzone.

If during the game press the reset (ctrl + F5) the game will load again, seen as spinning sector counter, but after loading the game hangs.

If during the game press the reset (shif + F5) the game will load again, seen as spinning sector counter, the game starts.

in emulator atari800winplus 4.0 we see another.
If during the game press the reset (F5) the game restarted, with no loaded, no hangs.

If during the game press the reset (shif + F5) the game will load again, seen as spinning sector counter, the game starts.

your comments.

breaker - 11 04 10 - 20:43

>Thank you, Mclane. I realized, fixed error ANTIC, right?

Yes, I don't know what affect this has on any games so you can see the change but it's another step in making the emu as correct as humanly possible so a huge thumbs up to Phaeron and the person who spotted the bug..

Mclane - 11 04 10 - 22:35

I have a weird theory re Dropzone that I think Phaeron will blast to bits :)

I'm wondering if a soft reset may in Altirra reinitialise some memory hence causing the fail and the full cold start being fine. I'll try a test in a min and see.

Mclane - 11 04 10 - 22:38 much for that...

Works perfectly here on all versions I've got.

Any chance of posting the version you use?

Mclane - 11 04 10 - 22:44

I've now tried all versions I could find so can only think yours is a bad crack that I don't have?

All warm start vectors so far are correct and return to a working game ie no loading needed. There are versions that if you cold start it seems to throw the disk out or not acknowledge it (I didn't check which).

If the warm start vectors have been tampered with it's the sign of a bad hack / trainer, maybe the main code was relocated at some point?

Just my thoughts..

Mclane - 11 04 10 - 22:52

Breaker, you mentioned the disk error again, have you checked it again as it seems to ok my end?

Mclane - 11 04 10 - 23:37

I used this version of the game Dropzone:

I'm interested in does not even crash the game.
I'm interested in other things.
Mclane, you noticed that in both types of reset the emulator begins to reload the game?
in the emulator, atari800winplus, when reset (F5) the emulator does not load the game, he seemed to instantaneous includes it.
loading occurs only when reset (Shift + F5), it is clearly seen as spinning sector counter

Check up on game boulder dash, for example, there the emulator does not hang.

breaker - 12 04 10 - 01:20

Simply put, when you click on F5 or Shift + F5 when the game emulators behave differently.
in altirra we see one, in atari800winplus we see another, even though doing the same thing.

breaker - 12 04 10 - 01:27

Sorry Breaker I get no sector counter activity, the game loads as normal, I hit CTRL F5 and it does a WARMSTART to the set vectors and just flips back to the title page, No loading....

Ie it does everything it should..

You might want to try something, it requires you to run Regedit from the run bar or go into the Windows dir and it's in there. I want to clear your settings in case there's corruption there, so make sure Altirra is shut down before doing any of this.

Please be careful if you use regedit, it's a nice tool but deadly if used wrongly.

When you run regedit you will see 5 HKEY_blah blah headings, one is called HKEY_CURRENT_USER. That's the one we want, expand it by clicking the little arrow next to it.

Now you will see a load of names, look for Software, expand that by doing the same and you will see lots of titles of things on your PC, notably their settings.

Look down till you see

Right click on it and choose Delete.

Now Altirra will be back to it's initial settings, see if that fixes anything?

It almost sounds like you are getting settings for beta 14 or before

Mclane - 12 04 10 - 04:05

Btw, forgot to say the game didn't hang..

Mclane - 12 04 10 - 04:06

Running Altirra with the /resetall switch is an easier and safer way to reset everything.

I was able to reproduce the behavior breaker saw by using the HLE and LLE kernels. It's probably a bug in the way I'm handling warm reset. It doesn't happen with a real Atari kernel ROM.

No word back yet on whether the change to ANTIC fixes the OP's problem... I'm curious too.

Phaeron - 12 04 10 - 18:08

oops, had not clicked there was a command line option to reset the settings...

Breaker can you confirm what O/S you were using when running Dropzone and the DD formatting just clear up the issue a little. No ofence to Phaeron but I don't use the HLE ever as I know it's not complete, I always just use XL or OSB as I have the best chance of a game working correctly which all do as far as I know...

Mclane - 13 04 10 - 01:32

I'm using bios sonovnom "atariXL.rom".
I also do not like NTSC and always put a PAL.

breaker - 13 04 10 - 02:01

it would be cool if Phaeron added button "Clear all settings".
I was once asked about this a long time, but ...

breaker - 13 04 10 - 02:04

Don't understand how if you are using a normal XL rom and system and hardware are both set to XL settings how you get those issues, it works 100% perfectly on mine doing the same thing..

Did clearing the settings help?

Mclane - 13 04 10 - 02:22

ups, I was wrong.
When I received this error I have stood "HLE kernel".
Sorry, Mclane

breaker - 13 04 10 - 02:31

uh, Phaeron, I understand that very much bother you, but ...
Please make a "warm reset" on the key F5.
I feel so awkward to press the keys ctrl + F5.

breaker - 13 04 10 - 02:41

He's been asked this before and said no as it's a key he has deliberately for the debugger.

Mclane - 13 04 10 - 05:31

but who cares, the effect of "Run" you can assign any key, such as F9.
all keys should go in order:
F1 help
F2 start
F3 sekect
F4 option
it is logical to add and F5 to reset, so much more convenient.

breaker - 13 04 10 - 15:20

I can see your point Breaker but at the end of the day it's down to Phaeron. He does supply the sources so it's there for you to customise. I myself have no idea what you need to build a version as I've never gotten into that side.

Mclane - 13 04 10 - 23:29

Phaeron, make sure no volcanic ash gets in the emulator!! :)

Mclane - 18 04 10 - 23:06

Alright, I've managed to overload F8 to free up F5, so F2-F7 should now match Atari800. I'm not moving F1 or F8-F10:

This version also contains some small optimizations to the NTSC artifacting engine and a fix for OPTION being held too long, which affected a couple of games that booted very quickly with SIO patch enabled.

Phaeron - 20 04 10 - 17:51

Thanks Phaeron, as user friendly as always.

Surely you must be close to releasing as a 1.6 final...There's a bucket load of changes from 1.5?

Mclane - 20 04 10 - 20:46

Hmmm...I could be wrong but I think F5 is mapped as a COLDSTART as is Shift F5 and Ctrl F5 is the old WARMSTART still?

Tested on Dropzone which for some reason started with graphic corruption but I cleared the settings and it still happened then suddenly it was ok??

Mclane - 20 04 10 - 21:14

Sorted out the graphic corruption, was a mix of being set to NTSC as default and HLE I think..

F5 still doing a full coldstart..

Mclane - 20 04 10 - 21:20

I'm having trouble loading non basic tape images in the latest beta, they work in 1.6 test 17 ok.

hardmanm - 20 04 10 - 22:20

Problem with loading non basic tapes with new beta.

hardmanm - 20 04 10 - 22:38

What ones Mark?, I'm not having any probs here, seems fine...Make sure it's not on HLE settings.

Lemme know, I'll see what i can do?

Mclane - 21 04 10 - 00:11

phaeron, many thanks for the update.
amazingly, there is now an icon in the emulator.

small mistake:
if you click the mouse click "warm reset" will warm reset.
but if I press the F5 key I get a cold reset, please correct.

yet I beg you, please do not let the final version of 1.6.
I very much hope that you will be able to fix the problem with the creation and recording to disk.

breaker - 21 04 10 - 02:06

All the ones in my gamebase, when i change it to point at the previous beta, they all work again.

hardmanm - 21 04 10 - 02:38

Already passed on the F5 problem but I am not sure what you mean by the creation and recording to disk.

If you mean formatting then it's fine?

Obviously I can't say if it works on HLE...

Mclane - 21 04 10 - 02:40

It seems thats the ability to lauch cas files through command line is broken

hardmanm - 21 04 10 - 03:04

I checked, the creation of DD drive was successful.
Write DOS files successfully.
Utilities atrutil and makeATR_v0.06 successfully opened created a disc.
emulator atari800winplus 4.0 successfully opened created in altirra disc, loaded DOS 2.5.

please accept my apologies phaeron.

breaker - 21 04 10 - 03:18

Hi Mark, is it possible somewhere that you have had a /nocasautoboot command line switch. that's the only thing I can see to stop the cassette booting, I've tried several cas games by command line here on the latest beta and all went in ok?

Mclane - 21 04 10 - 03:49

Easiest way to see if that is the culprit is to try one of the games and if it does not boot then when Altirra is up and running go to System/cassette and see if Auto boot on startup is unticked...

If yes then that's your fella...

Mclane - 21 04 10 - 03:52

phaeron, why did you change places keys?
on the keyboard atari office keys are as follows:
Help, Start, Select, Option, Reset, and it must comply
F1 F2 F3 F4 F5

please make a normal keyboard, as it should.

breaker - 21 04 10 - 15:39

It turns out that the Atari kernel reads the Start button later than Option, so when I shortened the button hold time to 1 frame past VBLANK it broke the cassette auto-boot. There's no problem with it being longer in that case since the kernel waits for a keypress anyway before starting the boot, so I've put in code to lengthen it back to 5 frames in that case:

As for the Start/Option switch, I reversed those because I thought it was more consistent with other emulators, but I didn't realize that Atari800 is backwards from Atari800WinPlus. WTF. I like A8WP more, so I've swapped them back. F1 for Help, however, I don't care about. Nothing used the Help key and if you want it it's on F6. I use fast forward MUCH more.

The F5 reset thing I just screwed up.

Probably close to 1.6, but I should let it stew a little bit for better taste. Also, I should prepare the updated hardware manual.

Phaeron - 21 04 10 - 16:16

I thank you, Phaeron so it is much better.
I can ask you about small addition in the following builds?

Add please memory size 16K.
Such memory size was on real atari and is present at all other emulators atari.
It is a trifle, but it can it is useful.

do not let the final build of 1.6, let it be at least 20, even 30 beta releases, but the emulator will be brought to a higher level.

I'll be with you till the end and help than I can.
Good luck.

breaker - 21 04 10 - 17:47

Cheers for the new build..

As for 16K, as far as I remember there are no 16K and below games.

Beta wise there has to be a cap at some point, there are people who will not use beta's in case there are bad bugs still present. Also is it that you think if Phaeron releases a 'final' he won't work on the emulator for a while?

I doubt that would be the case as Phaeron is one of the quickest updaters in the emulation circuit and we are very grateful for that...

Mclane - 21 04 10 - 19:19

Mclane, saying final, I was referring to the stable release 1.6 and not the end of the work on the emulator.

Did not you used to say that even if only 100 tests, it appears important that the work continued

What about memory size, I know that there were even Atari 8K, but I do not see a single emulator atari with 8K of memory.
16K is better to let it be.
although this should solve phaeron.

breaker - 21 04 10 - 19:30

I believe there were a lot of games that could run in 16K, as that was a common configuration in the early 400/800 machines. What's not so clear is how many games will ONLY run in 16K, and fail if there is more RAM. That's not likely to be common, especially since it's hard to write any software on a machine that small (it's not like you could write them on an emulator like we do now, unless you were a big company). Otherwise, pretty much the only reason to have a 16K only option is if you want to write software that can run in 16K and need to verify it, which is not common either.

If we're talking about emulation completeness, on the other hand, there are a lot more configurations in the Atari 800 -- just about every configuration of up to three of those funny 4K, 8K, and 16K RAM cartridges, in fact. Some of those configurations aren't even contiguous, leading to hidden memory that the OS can't see. Just about all of them except 48K are pretty useless at this point, though.

The Atari 5200 also has a 16K configuration, but there's a lot more required than just a memory map change. For instance, the input setup is completely different, there is no PIA chip, and the hardware registers are at different locations.

Phaeron - 21 04 10 - 19:35

Thanks for the explanation.
I hope you implement this in future builds?
Suddenly it is useful, just in case ...

breaker - 21 04 10 - 21:21

Phaeron thanks for the quike beta updates.
And this is a fine emulator i like it.
The atari 800 win plus i used before i used both but altirra is now the number 1 for me.
Only i hopen someone program it for nokia's :).
I hope that you do a long time program altirra my very special thnxx for the great work.
I fill my email adress you can reach me all so for other atari 8 bit user :).
Do you now Mr. Atari ? he do check that option he build myide and program os to.

Gr. Marco Kersten from holland.

marcokitt2000 - 23 04 10 - 05:57

Phaeron, I'd remove his address before he gets email farmed..

Marco, not the best idea to put your email address up on a public forum...

Mclane - 24 04 10 - 05:30

New version, or rather, release candidate for 1.6:

Not much changed -- I rewrote the paste function so it works faster and more reliably.

Phaeron - 24 04 10 - 10:30

memory size not added :(
phaeron, can I ask you about a small change?
Can you add a feature to take screenshots in the emulator?
I would like it to be view ---> save screenshot.
very necessary that the image stored in jpg or bmp.

breaker - 24 04 10 - 11:13

No, I want to get 1.6 out the door soon. If you want it that badly, you need to justify it, especially since there is already View > Copy Frame to Clipboard.

Phaeron - 24 04 10 - 11:34

RC candidate good to go Phaeron..

Breaker, you didn't take long to break the promise.....You have asked for screen shots a few times before and already asked re the memory. If Phaeron thinks it's a worthy addition he puts it on his todo list, it's not forgotten as you seem to think. How do I know, the screen size and position was a feature asked by myself many moons ago, one day it turned up, that's the way it works.

Also, if Phaeron has said he does not think a feature is worth writing or needed then do you think asking multiple times is going to make it more likely or less likely to get added.

AFAIK, Phaeron has never turned down a solid emulation or coding related request, that's the best you could ever wish for.

Mclane - 24 04 10 - 23:14

phaeron, Mclane, do not take offence, but you should understand that that way of creation of screenshots which is used now, very inconvenient.

I presented emulation atari at us, on emulation sites of Russia, your emulator recognise as one of the best.
But thus practically all tell that altirra very inconvenient and few-functional the emulator.
Many at all do not understand that such "View> Copy Frame to Clipboard.", ask "in this emulator it is possible to create screenshots?".
screenshots needed for the base game, and we have to use for this Atari800WinPlus, instead no altirra.

breaker - 25 04 10 - 01:19

Breaker, I can't speak for Phaeron, it's his emulator and he alone chooses what is in or out but as someone who beta tested numerous emulators and Atari800win and offered some of the features that went into it (See Paul Irvine in the credits) I'm aware of the sort of stuff that's classed as important in the development of the emulator.

Firstly the core, normally an internal debugging system, then devices, input, then it's emulation fixes, tweaks and the last but not least are the 'toys' ie non essential but fun additions like video filters, save states, sprite viewers, cheat stuff, video and wav saving etc etc..

Now if you look at that list you will see that Phaeron is well into the list already, he has already added many 'toys' but point of reference must always be that the emulator emulates the hardware as closely as possible. There's little point in having a screen shot command if what you see on the screen is wrong.

The view/copy frame to clipboard is essentially what you are asking for already, once that is clicked just open up your favourite art package and 'Paste' it in, you can decide what you want to do with the image there and then.

Altirra is any thing but inconvenient, Altirra's user friendliness is very high but just because you want a screen shot command why should Phaeron stop work on essentials, that itself is inconvenient. I'm sure Phaeron is proud and happy with the emulator and wants it's users to have the best / easiest time with it but it's his project and it's looking bloody good...

Mclane - 25 04 10 - 06:10

1.6 final is out (

Phaeron - 25 04 10 - 15:02

Mclane, I understand everything, but I must say that all emulators should be made as convenient and accessible to anyone.

I think you would not like to go in the car, which lacks half of the devices, and some details posted God knows where.
so, comparing the emulator and the machine.

Although, I must agree, in altirra made the most important.
errors in the emulation is practically no, I'm becoming increasingly difficult to find new bugs, and it pleases.

breaker - 25 04 10 - 15:45

Breaker, if I use your comparison re the car then Altirra would be a perfectly drivable car with excellent performance but missing an ashtray or the fluffy dice. What you have to understand is that it's an emulator first and foremost, it's not marketed as a graphics studio nor a sound recording device, it's an emulator.

Most of what you want isn't emulator related, what you are after are tools for sprite / font / screen ripping, cheating and sound adjustment. These are mere toys which I would like to see myself but not before emulation is fully addressed. The one thing you are missing is patience, if you have been listening then you would have heard Phaeron say that he is getting close to having hit the wall as to speak regarding the emulation.

So he's near as he can be with the way it can work bar completely starting from scratch, so as he needs less time on the hardware he just might have time to THINK about the previous requests. He might look at what's been asked for and see if he wants to code them in OR NOT.

What worries me is that you seem to forget that you are not paying for this emulator, if you were then the author would be obliged to take on requests and add them, but as Altirra is free you have no right to any additions, anything is down to Phaeron, his free time and his desire to code. Constantly nagging him may reduce his desire entirely and then people like me and others have a dead project to play with knowing it won't be updated because he got fed up with nagging.

So, do you want a dead project or can you just wait and see if you got lucky with a request?

Bottom line, you make a request, he reads it, you hope he likes it. If you are lucky you see it, if he does not like it then you be grateful for what you already have.

Don't bite the hand that feeds you...

Mclane - 25 04 10 - 20:07

Mclane, I was tired to argue with you.
Again, emulation atari in emulator altirra done superbly.
I practically do not see what can be further improved.

there is certainly some way and not working cartridges, there is no support *. bas file, but this detail.
well, the emulator is ready and the author in any case have to add everything else.
simply because they have nothing else to do.

I prefer to live and emulator developed and therefore propose the development emulator.

breaker - 25 04 10 - 21:22

Well just wait and see what comes, me, you, Phaeron and every other person who has contributed idea's all want certain features, now it just wait and see if you are lucky, Phaeron is more than aware of what's been asked for and why.

Until then you always have Atari800win plus as a fall back..

Mclane - 26 04 10 - 00:18

Mclane, I was not going to use the emulator atari800winplus.
I really love the sound in the emulator altirra.
and another reason I use windows 7 x64, atari800winplus gives the wrong palette in full screen.
so my choice is altirra.

breaker - 26 04 10 - 12:48

All I can promise is that feature requests go on the master list -- other than that, they'll show up when they show up.

Now if you lived in a physically closer location, there would be opportunities for bribery... but even then, the difficulty would be that I don't drink.

Phaeron - 26 04 10 - 16:01

You don't drink, I now believe you are a robot! :)

Mclane - 26 04 10 - 21:37

yes mclane you are right about email adres but it's a gmail :) but thnxx.
i see only few people write here they can use my email adres.
i have buyed for 10 euro a 600xl orginal and 800xl :) with a damaged old 1010 tape and a 1020 plotter some books :)

marcokitt2000 - 28 04 10 - 06:34

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