| br>I spent the afternoon checking every solder joint and connection on both boards. Polarity of every component is correct where necessary.
I pulled all the ICs and swapped them A-B where I could, but no change in the operation of the module.
Section B runs as expected. When Slave B>A is engaged, it also switches to the rate as set by RATE A, even if RUN B is off, so I’m thinking the logic of A is getting thru.
Section A RUN control pushbutton will go on or off as needed. But regardless of RUN A setting, the PB led on step A1 stays on solid. None of the others light up as stepped (A2-A8). The only clue I have to the operation of A is when I push the reset (momentary) – in the pressed position, it briefly lights the current step and resets the bank to step zero upon release. So if I have LENGTH A pot set to a value 1-8, the last step will briefly illuminate. The PB LEDs will work on every step of section A. If I continue up setting LENGTH A up past 8... to 16, the individual steps in section B also briefly light. So I think all the PBs are working ok.
So I’m down to the function of the ICs, I think – probably on the logic board, because I already traded positions of the Controller Board ICs with no apparent changes as a result.
1) could the big 40 pin IC be faulty? Is it flashed at the factory and has maybe become corrupted?
2) I had extra TL072s and changed them all, so they’re not the problem. ..I think. Also changed TL074.
3) I made sure to get the TLV2374 specifically, all other chips are also as listed on the BOM. (all from Mouser)
4) and i have no clue what the other ones do...could any of them be at fault?
I took a video of the problem a few days ago...here's a link to private video
take up golf instead? br> br>