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Re: Oricutron and illegal opcode 80

Posted: Fri May 10, 2019 8:53 pm
by Symoon
iss wrote: Fri May 10, 2019 8:43 pmall rights and decisions belong to the author Xeron!
Sure! Just to make it clear: I'm just a newbie trying to understand, and not willing to say anyone "do this and do that, 'cos I'm too lazy to do it myself" ;)
Else, my developer builds are fresh updated ;).
Thanks! Cheers!

Re: Oricutron and illegal opcode 80

Posted: Sat May 11, 2019 11:20 am
by Symoon
Symoon wrote: Wed May 08, 2019 10:20 am I noticed something strange in the 1st part of Harrier Attack (loading screen). Apparently, the Atmos version has a bug; on the original tape or transfer bug - I still need to check that but so far I think it was on the original Atmos version of the tape.

Here's the bug, as shown by Oric Explorer:

Code: Select all

$06B2  A9 10      LDA #$10      ..   
$06B4  8D 61 06   STA $0661     .a.
$06B7  A9 07      LDA #$07      .. 
$06B9  09 62      ORA #$62      .b **** => BUG, was 8D 62 06 (STA 0662) on the Oric-1 version ****
$06BB  06 A9      ASL $A9       .. 
$06BD  80         ???           .  
$06BE  8D 63 06   STA $0663     .c.
$06C1  A9 BB      LDA #$BB      .. 
Just for the record: I have checked an original Oric-1/Atmos tape, on both sides, and the bug is here. So, an unoticed bug using an illegal opcode was duplicated in (all ?) the Oric/Atmos versions of Harrier Attack ;)

Re: Oricutron and illegal opcode 80

Posted: Sat May 11, 2019 12:05 pm
by iss
This is really strange how $8D become exactly $09... Oric-world full of secrets and mystery :D!

Re: Oricutron and illegal opcode 80

Posted: Sat May 11, 2019 1:11 pm
by Symoon
iss wrote: Sat May 11, 2019 12:05 pm This is really strange how $8D become exactly $09... Oric-world full of secrets and mystery :D!
Since the tape signal is not faulty here (same on all recordings), and since $8D and $09 a far one from another binary speaking, my guess would be: mistake while programming the Atmos version! (just a guess though ;) )
Scuba Dive had a programming bug in its Atmos version, so maybe Durell made those new versions in a rush ?

Re: Oricutron and illegal opcode 80

Posted: Sat May 11, 2019 1:51 pm
by Steve M
The oric-1 version seemed to have a few bugs as it would crash at odd times. I was never sure if it was programming error or dodgy tape loading though.

Is Oricutron being updated? I've had some odd thing happen with it - it often crashes to the editor screen - but I'm not aware of updates still being down. I thought it had been left with no further updates?

Something I noticed was if you load a disk you can't then load a tape.

Re: Oricutron and illegal opcode 80

Posted: Sun May 12, 2019 10:19 am
by christian
Steve M wrote:Something I noticed was if you load a disk you can't then load a tape.
I opened an issue about it some time ago and I solved the problem, but never sent the Pull Request :oops:

Re: Oricutron and illegal opcode 80

Posted: Sun May 12, 2019 12:07 pm
by iss
christian wrote: Sun May 12, 2019 10:19 am
Steve M wrote:Something I noticed was if you load a disk you can't then load a tape.
I opened an issue about it some time ago and I solved the problem, but never sent the Pull Request :oops:
@christian: Yep, one year ago :). If you have solution let fix it.
BTW, I've checked and it seems to work but not always, it's strange ... :o

Re: Oricutron and illegal opcode 80

Posted: Mon May 13, 2019 7:34 pm
by Vyper68
Would anyone be able to make another .tap file of Harrier Attack with the illegal Op Code amended? I have a French Atmos that seems to have a factory fitted 65c02P4 and it freezes after loading the first part of the Atmos tape file and it has been suggested that this Op Code is the cause of this.
It is an odd machine as it has two RAM chips like the C64c and not the usual 8 4164's.

Re: Oricutron and illegal opcode 80

Posted: Mon May 13, 2019 7:49 pm
by Symoon
Vyper68 wrote: Mon May 13, 2019 7:34 pm Would anyone be able to make another .tap file of Harrier Attack with the illegal Op Code amended? I have a French Atmos that seems to have a factory fitted 65c02P4 and it freezes after loading the first part of the Atmos tape file and it has been suggested that this Op Code is the cause of this.
It is an odd machine as it has two RAM chips like the C64c and not the usual 8 4164's.
Get WAVs here:
dl.free.fr/qfY6YBBPA
(Standard speed, and Novalight)

And TAP:
harrier-atmos-bug-corrected.tap
(11.53 KiB) Downloaded 333 times

Re: Oricutron and illegal opcode 80

Posted: Mon May 13, 2019 8:49 pm
by iss
Vyper68 wrote: Mon May 13, 2019 7:34 pm...French Atmos that seems to have a factory fitted 65c02P4 ... two RAM chips ...
@Vyper68: Very interesting! This is for sure not factory machine. Can you take and attach some pictures?

Re: Oricutron and illegal opcode 80

Posted: Tue May 14, 2019 1:28 am
by NekoNoNiaow
Symoon wrote: Wed May 08, 2019 1:03 pm Anyway it's interesting, because if this file is from a different source, it confirms that the bug is on the original tape, hence Durell had a very unreliable masters for their tapes duplication (there were also strange things in Scuba Dive IIRC).
I initially thought that this may be part of a protection scheme but "flaky bits" are put into data and not code because of the risk of crash if opcodes are wrongly interpreted.
In any case, I am with @chema: emulators should simply act like the original hardware. ;)
Dbug wrote: Fri May 10, 2019 7:37 pm I know I'm going to feel annoying like a scratched vinyl, scratched vinyl, scratched vinyl, scratched vinyl... but I really, really, really want the people working on Oricutron to come up with a scheme for version number and change list.

It's specially important for when reporting bugs and asking for features.
I agree. The issue is that the Oricutron author is too busy to release official versions so every version that is currently released is done so independently either by @Jede or @Iss (and possibly some others I forgot (sorry!)). It would really help if Pete Gordon could give rights to @Jede or @Iss to release new versions (cf https://github.com/pete-gordon/oricutron/issues/103).

Re: Oricutron and illegal opcode 80

Posted: Tue May 14, 2019 12:03 pm
by ibisum
Apropos Oricutron builds - I'd be happy to assume package maintainer/release duties for Oricutron on MacOS.

Re: Oricutron and illegal opcode 80

Posted: Tue May 14, 2019 12:26 pm
by Vyper68
Here are some pictures of my Atmos for you to look at, the Transistor is a BC237 i think as it says C237. Looking at the 65c02 i think it was fitted later as the date code is 8813 so it's not factory fitted.

Image
Image
Image
Image

Re: Oricutron and illegal opcode 80

Posted: Tue May 14, 2019 12:50 pm
by Vyper68
The BugFixed Atmos .tap and .wav files work with this Atmos both the standard and Novalight versions are fine now. So thanks to Symoon for doing that for me. :D

Re: Oricutron and illegal opcode 80

Posted: Tue May 14, 2019 5:03 pm
by mikeb
Vyper68 wrote: Tue May 14, 2019 12:26 pm Looking at the 65c02 i think it was fitted later as the date code is 8813 so it's not factory fitted.
Your board seems to be date coded 83 44 (on the back), the ULA is 83 12, but the DRAM chips (only 2 of them? 4464 x 2?) are from 1985 (8527).

That's not a board configuration I've seen in real life, must be French re-spin to use better available, higher density chips.

Also, your CPU is in a socket, and I don't think originally Oric socketted the CPU, much to my annoyance having to desolder them for repairs :(