Today I fixed the problem I was having with the new batch using the new PCB spin hanging. It turned out to be a construction error by yours truly, with a transposed decoupling capacitor and pullup resistor on all three boards. But it took most of the evening to find. The symptom was that after between 1 minute 40 seconds and 1 minutes 55 seconds the units would hang. In fact, it turns out the unit went into a hardware reset as it was the MCU’s reset pull up resistor that had been transposed with a capacitor. Really frustratingly, on the in-circuit emulator in debug mode it worked perfectly as the reset pin is directly controlled by the debugger.
I also did some work on the gain distribution testing…
