2019-03-01 02:05 PM
It looks like I made a fatal mistake by connecting the NRST pin to the PA0 pin on an STM32F778AIY. This is a part with no internal voltage regulator for the core so the PA0 pin acts like a power on reset. This hasn't caused problems with power cycling but it does seem to cause a problem with using the SWD debugger or programming flash via JTAG. I can use Cube Programmer to connect to the device fine as long as I use the Core Reset option, but as soon as I try to program a flash, I see the NRST pin driven which in turn drives the PA0 pin. This causes all kinds of problems.
Anyone see this before or have any idea how I can keep NRST from being driven during programming?