Yamaha DM2000 v2 issue

[tadejm]

Hello!

I am the owner of the "good old" Yamaha DM2000, which I have for over 17 years, I only use it in the studio. It worked without problems until about 2 years ago. But then it started to appear that sometimes in the middle of work it throws it into "Update Mode" or writes "Protocol Error" on the display. But sometimes it just blocks (all meters, all controls, but the sound goes through normally).
After every such error, if I turn it off and turn it back on after a few seconds, it works normally again. But I never know if it will work for one minute, one month or one year

Today I opened it (1000 screws LOL) and resoldered the complete CPU board (I assumed some kind of cold-joint around the CPU or memory)...

When I put it back together it worked for about an hour and froze again.
So I didn't fix anything.

Does anyone have any experience with such "ungrateful" issues? If I could locate WHAT the error is, I would fix it 100x already.

BTW, the power supply is stable, the battery is new.

Suggestions are welcome!
Tadej

 

[Philbo King]

Likely due for a re-cap job at that age, but it would be good to monitor all the DC supply voltages while it is acting up.

 

[tadejm]

Likely due for a re-cap job at that age, but it would be good to monitor all the DC supply voltages while it is acting up.

Thanks for your answer!
Do you mean, re-cap power supply or (even if the voltages are correct and stable and caps look ok "on the eye")?

 

[Philbo King]

If the power supply DC voltages are correct and have very low ripple (AC content) it means that part isn't broken.
My philosophy is to not fix things that aren't broken. But some people do it to old gear as a preventive measure.

 

[tadejm]

updated news...

Even though it didn't seem to be a PSU problem, I replaced all the capacitors on it.
I also (due to the possibility of dry soldering) re-soldered the entire CPU board, sub-CPU board and DSP board.

When I was already happy that it was working, after a couple of hours the prompt "Waiting data..." started again.

I am slowly running out of ideas…hmm….

I found something on the same topic on another forum... Otherwise for the 02R96 (which is practically the same, only smaller than the DM2000).

https://recording.org/forum/pro-audio-repair-modifications/yamaha-02r96-dsp7-atsc-error-bugs

I still haven't given up. )

 

[tadejm]

Hello!

Another update

I found that the problem is the microprocessor on the CPU board. First of all I replaced the SRAM and DRAM modules and there was no change.
Then I replaced the microprocessor and the mixer has been working for approx. 12 hours without being "thrown" into update mode or freezing.
So, I can almost say for sure that the problem is the microprocessor!

Now I would like to ask for help... Namely - the mixing console, despite the fact that it is working, everything works slightly slower than before (loading menus, drawing graphics, changing layers, ...).
In the service manual it says that the CPU is: SH7709A.

The original in the DM2000v2 is the (SH-3) HD6417709A-F100B processor.
Because I couldn't get it anywhere, I ordered from aliexpress the same that my 02R96 has, which is: (SH-3) 6417709A-100V.

(BTW: The 02R96v2 and DM2000v2 CPU board looks identical, except the multipin connectors are different on the 02R96 and on the bottom side of the board, and of course the microprocessor, DRAM and SRAM modules - for RAM there are several alternatives listed in the service manual, and for the microprocessor only the designation SH7709A.)

Is it possible that this processor is too slow for DM2000?
Could I hypothetically order a faster one, e.g. HD6417709A-F133B (I guess 100 or 133 means the frequency (MHz))?

Does anyone know what microprocessor is in the DM2000 VCM series??

Thank you!