I’ve been troubleshooting a 01/W, not FD or Pro with ROM v.62.
In the state I acquired it, all patches and combos gave multiple notes following noteon, sometimes like a delay, and occasionally with random, unplayed notes following, I first thought the error was taking place in modulation/effects, as initializing internal memory (RESET/3 on power) delivers clean albeit boring, unnamed tones, and all keys are fully functional.
Reloading patches/combi/sequences from the internal ROM chips brings it back to the unusable multiple delay/random notes problem. Initializing and downloading even a single patch over sysex results in the same issue.
-ROM chips have been removed and reseated, but given successful initialization, I feel they are fine.
-CR2032 has been replaced, but the keyboard was already maintaining the (suspected) corrupt patches after restart.
-I have played with editing initialized patches without problem.
-I have identifed no swollen or leaky caps or broken traces.
My suspicion at this point is faulty SRAM, but unless I’m missing something, these chips are all surface mounted, which probably renders this a controller for another synth.
Any ideas, similar experiences, or am I missing something obvious?
For a better understanding of your logic, speculation and assumptions, could you provide links to the documents, elements of which you voice here…
Please understand me correctly - a very limited number of people understand the structure and details of your equipment, and it is not worth forcing them to search for documentation of your equipment by wasting their time on the forum.
Note that I can’t actually run a diagnosic program as documented, both because I don’t have a diagnostic card, and because the original 01/W doesn’t have a key combination to lauch diagnositc mode.
First of all, I would check the quality of the power supply +5V (and 12V - although this applies to the audio path) and check the condition of the internal battery.
Based on the experience of synthesizers of these years of production, often a low voltage of the internal battery is the cause of broken RAM-memory, due to which some bytes are lost or written incorrectly.
The second gentle option is to try to rewrite the latest operating firmware through a programmer. The reason may be in the EPROM, as they comment on the video at 4:48
Very helpful. I’ll take those steps (just replaced internal battery, but I didn’t test the power supply).
If not, I guess I’ll try to overwrite the EPROM: I do have the latest version installed, but it’s possible that it has been corrupted.
You know what, @sargfowler, that problem sounds almost identical, and may confirm my original suspicion–especially given that sysex results in the same results as importing from ROM, alonside the fact that initializing the patches (without effects) gives me an otherwise usable keyboard. I really wasn’t looking foward to desoldering those chips and replacing them, but it might come down to that. Thanks for making that connection.
Helpful video! On the 01/W, the sound is a little different, but the problem appears to be the same. I’ll look for equivalent chips–my board has D41464V-10s, but I’ll poke around for an available equivalent. Thanks!
