Re: AW: Mess Emulator für diverse Schachcomputer ist fertig!
 

Thanks for the bug report, I fixed it (bug was caused by me, too).
I changed it back to a "beeper". Does anyone know the freqency(pitch) of the beep? Actually a simple sound recording will do.

AW: Mess Emulator für diverse Schachcomputer ist fertig!
 

Hi hap, nice you're here!

I have two Mondials, I measured them with a guitar tuner.
Lower Serial one (older) : C6 - 1046.5 Hz
Newer: C7 - 2093 Hz

Re: Mess Emulator für diverse Schachcomputer ist fertig!
 

Danke =)

Now I'm even more curious! So it's a (small) hardware revision. Was the ROM updated too?
1046.5hz with a guitar tuner, if I had to guess, it's actually 1024hz, maybe divided from a 32768hz XTAL.

AW: Mess Emulator für diverse Schachcomputer ist fertig!
 

I don't think the rom was updated, but I suspect it's an active beeper with a fixed frequency, so they maybe just took a different one.

I can't (and won't) read out the roms, as they are soldered to the board.

AW: Mess Emulator für diverse Schachcomputer ist fertig!
 

Hier ein Bild mit dem Innenleben des (älteren) Mondial, mit dem schwarzen Beeper, vorne das ROM HGS 10 470 00.

Re: Mess Emulator für diverse Schachcomputer ist fertig!
 

Usually, a beeper doesn't oscillate by itself, it has an external circuit to automatically turn it high/low(like a 555 timer, or XTAL+divider), and then another (software controlled) line to enable/disable it.
*edit* top-left corner looks like a small XTAL, probably 32768Hz? for IRQ and beeper.

BTW that CPU is 1MHz, I guess it implies that the 1st Mondial is 1MHz, 2nd version is 2MHz.

AW: Mess Emulator für diverse Schachcomputer ist fertig!
 

hap, did you see this message?
https://www.schachcomputer.info/foru...postcount=2981

Re: Mess Emulator für diverse Schachcomputer ist fertig!
 

I saw you discussing it but I didn't see this post with the details. Thanks for reminding me, I'll update the driver.

Re: AW: Mess Emulator für diverse Schachcomputer ist fertig!
 

I asked Sandro about it: he found the icons at offset 0xf77 of bw1_819n_u4.u4
Then he made a script to correctly map the pixels.

AW: Mess Emulator für diverse Schachcomputer ist fertig!
 

hap, both Mondial solve a problem in the same time, I measured both near an AM-Radio, and the frequency is indeed near 1MHz.

As for the active buzzer, look here:
https://www.addicore.com/Active-Buzzer-5V-p/146.htm

Edit: The beep could also be generated with the 74LS14 and 74LS74 next to the silver inductor (or XTAL?) top left.