Bug in the z80 emulation or in the TR HW ??????

Page 1/2
| 2

By ARTRAG

Enlighted (6464)

ARTRAG's picture

12-08-2008, 23:35

I need to state if the out (c),0 opcode exists in real TRs (in z80 mode) or not.

Apparently my TR A1GT (the real HW) does not execute the code undocumented out (c),0
corresponding to ED 71, but only the documented out (c),a, corresponding to ED 79,
even when in z80 mode !!!

The fact is that BlueMsx and OpenMsx both implement that opcode when on TR mode !

Where is the error ? In the emulators or in my own HW ?
Is the out (c),0 opcode supported by any TR ?

Are there known cases when out (c),0 opcode is not supported ?
Is there any TR owner willing to do some tests with the code I'll send him ?

I have two roms to use with Pasos SCC Flash rom

help!

Manuel, Daniel did you face the issue before ?

The files are here:
https://sites.google.com/site/testmsx/Home

Login or register to post comments

By NYYRIKKI

Enlighted (5687)

NYYRIKKI's picture

13-08-2008, 00:01

I did some testing, and it seems that #ED, #71 does not do I/O in R800... In Z80 it does OUT (C),255 !? (Tested on A1GT)

By ARTRAG

Enlighted (6464)

ARTRAG's picture

13-08-2008, 00:19

Yes, I confirm
From my files you see that OUT (C),0 works like OUT (C),255

(on my A1GT naturally)

By NYYRIKKI

Enlighted (5687)

NYYRIKKI's picture

13-08-2008, 00:27

I actually did not try your files, but good that we agree...

By ARTRAG

Enlighted (6464)

ARTRAG's picture

13-08-2008, 10:07

PS

The files in the link are a special version of the 2K game Intruder.
It is worth a try, as they support sfx done with PCM samples (8 bit/sample and 7,6KHz sampling freq.)

By jltursan

Prophet (2413)

jltursan's picture

13-08-2008, 10:29

Here's a reference of the undocumented opcode OUT (C),0 and the R800:

AS documentation

Seems that this opcode is one of the most incompatible ones as I'm aware that the Z80B also has problems with it.

By ARTRAG

Enlighted (6464)

ARTRAG's picture

13-08-2008, 10:54

If I understand correctly, the z80 inside the TR is fine, the problem could be in the I/O circuits of the TRs

PS
have you tested my roms ?
Big smile

By jltursan

Prophet (2413)

jltursan's picture

13-08-2008, 11:21

I'm at work right now, I'll try to test them later at home and since today I've received my new TR-GT I'll be able to test them on both machines Big smile (until I get rid of my now obsolete TR-ST :-P).

Btw, the SFX are astouding!, they could really set a new quality standard in MSX games; but,....wait....I'm hearing elephants and monkeys when robots die???? LOL!

By ARTRAG

Enlighted (6464)

ARTRAG's picture

13-08-2008, 11:28

Well, the choice of SFX was intended just for testing
Smile

As the MOAM project is in the jungle I was looking for jungle sounds
beeing at work i was able to use only sjasm and not HiTech C,
so I worked on the sole game in ASM I had.

Now I have to do a choice between:
1) finding appropriate SFX for Intruder
2) porting the SCC SFX plaier in MOAM

Tongue

By jltursan

Prophet (2413)

jltursan's picture

13-08-2008, 12:52

1) finding appropriate SFX for Intruder

You *must* use the berzerk original sounds, they're great!

By JohnHassink

Ambassador (5507)

JohnHassink's picture

13-08-2008, 13:57

Chicken! Fight like a robot!
Big smile

Page 1/2
| 2