Offline
Russia

Hi everyone.
Yesterday I got postage - 2 new game boys and one of them has very strange bug - 1st pulse channel plays whatever it wants. I was surprised when I saw Nintendo logotype with new turn on sound. Note is the same but wave forms and some parameters chenged randomly. So the question is: What is going on? What contants should be checked, I have soldered each contact twice< but I don't know which contact should be checked.
This is reproduced with different screen shels and different cartridges. not reproduced on other game boys.

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Sea of Souls

Doesn't sound like a bug, sound more like the data registers within the cpu are broken. Maybe it took a zap or something.

Im still curious thuogh. Can we get a video with sound and a pic of the CPU's pcb?

I think nitro may have a ROM which displays written and read registers on screen. Might be worth looking into.

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Russia
Orgia Mode wrote:

Doesn't sound like a bug, sound more like the data registers within the cpu are broken. Maybe it took a zap or something.

Im still curious thuogh. Can we get a video with sound and a pic of the CPU's pcb?

I think nitro may have a ROM which displays written and read registers on screen. Might be worth looking into.

here is photos of game boy: https://photos.google.com/share/AF1QipM … 91VENvSjBB

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Sea of Souls

What CPU revision is it? It says just below the cart connector, between the battery contacts.
You can read this through the battery compartment if you already put it back together.

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Russia
Orgia Mode wrote:

What CPU revision is it? It says just below the cart connector, between the battery contacts.
You can read this through the battery compartment if you already put it back together.

On CPU it's marked: DMG-CPU B 9311 D; On bottom side DMG-CPU-06

Offline
Russia

Ok. I used this tests https://github.com/stanislavche/gb-test … /dmg_sound
here is a list of errors
--------------------------------
NOT PASSED TESTS:
--------------------------------
dmg_sound.gb Failed; #12 :1;
interrupt_time.gb Failed; 7F8F4AAF
cgb_sound.gb Failed: #8 : 1; #9: 1; #10: 1; #11: 4; #12: 2;



Last edited by stress_tn (Apr 2, 2019 11:32 am)

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Sweeeeeeden

CGB_SOUND is a test for GBC and it should fail exactly like that on a DMG. This is expected so no problem there. INTERRUPT_TIME again is a GBC only test ROM, and although I haven't confirmed it, it should likely fail on DMG as well. DMG_SOUND failing is suspicious, but ultimately probably unrelated since the test that failed relates to the wave channel and the glitch affected channel 1 as you said.

Do you have a recording of the startup sound or something else that showcases the bug?

I may be interested in acquiring this 'boy for research.

Offline
Russia
nitro2k01 wrote:

CGB_SOUND is a test for GBC and it should fail exactly like that on a DMG. This is expected so no problem there. INTERRUPT_TIME again is a GBC only test ROM, and although I haven't confirmed it, it should likely fail on DMG as well. DMG_SOUND failing is suspicious, but ultimately probably unrelated since the test that failed relates to the wave channel and the glitch affected channel 1 as you said.

Do you have a recording of the startup sound or something else that showcases the bug?

I may be interested in acquiring this 'boy for research.

Sorry for delay. Here is an example: https://chipmusic.org/stress_tn/music/p … ch-example
It consist of 3 parts:
1) Power on, logo melody;
2) How it sounds into a track;
3) 1st Pulse channel play's C5 note with new clear instrument;

Last edited by stress_tn (Apr 6, 2019 10:42 am)