Going back to electronic after a 20 years break

Lately, i updated lnDSO150 to v2.3, in particular its build system to be in sync with how i do things nowadays. The main goal is to easily switch between GCC and CLANG-17 (   arm or riscv ) The lnDSO150 has one variant (the FNIRSI one) with less flash ( only 64 kB), so i could use every flash gain possible Using clang + lto DID provide a nice size reduction (final size was ~ 50 kB for the fnirsi build) and at first it seemed to work alright. At first. Then, i realized that it made some underlying problem appear due its aggressive optimization. In other words, the bugs were there since day one, but hidden because the software was losing the race against the hardware every time. A couple of examples : - On the DSO150, some of the screen GPIO are reprogrammed as input to scan if  buttons have been pressed. If you flip the gpio too quickly, the button MAY keep the last state it was when used as output, causing random fake key pressed. Adding a couple of nops fixed the issue. - Sim...

 Finally got the PCB (that was my first one) As expected a couple of mistakes (selected footprints too small etc..) but it works! Since the CH32V303 is running at 140 Mhz, it is faster than the bluepill based one. For reference, i did the same PCB for a GD32F303, and it was more complicated. The ch32v303 version is much simpler, no need for extra glue. The chip, a 8mhz crystal, couple of resistors and caps and that's it. I've also ran into a false problem. The normal BMP  just reboots when it asserts, so you dont see that happening. The lnBMP halts when it asserts, took me a bit of time to realize that was not due to a problem i introduced.