Thanks, guys -- keep those ideas coming!? ? I bought NEW, longer ribbon cables and was very careful connecting them.? ?I think I'm doing something wrong that the Pi2 couldn't display the SBITx screen -- it displayed everything else just fine!
It has been a long time coming, due to my ignorance,? and terror of losing yet another Raspberry.....but finally I have the software RUNNING again? ? ?I started with a Raspberry Pi 2 (all I could get cheaply that I was willing to RISK) -- hours of learning in order to be able to recompile for its operating system (there is probably a better way)? until it compiled? ?Running showed I2C errors (since not connected to anything!).? ?Verified the 3.3VDC regulator on digital board still putting out 3.3.? ?Found a 9V small power supply to run the main board to a small degree and verified the 3.3VDC regulator THERE works also -- so suspect the codec and si5351 survived.? ?
Once reconnected, no more I2C errors -- BUT NO DISPLAY from the sBitx program on a new touchscreen.? ?WHY?? ?I have no idea.? BUT NOTHING DESTROYED.
Since nothing destroyed, replaced the Pi 2 with the Pi 4 and original memory card -- and bingo!? ?I got a display and the software appearing to run.? ? Have not verified function yet, but I've spent many hours fiddling with the RF portion of this radio, so less worried about that side.
If anyone can tell me why I couldn't get the sBitx to display on the Pi 2 version, I'd be delighted. Progress, after so, so many months.?? Gordon KX4Z