CH32V203C8xx : no breakpoint ? :(

 A couple of months back i bought some CH32V203 on ebay. 

Why ?

They were cheap, they are pin to pin compatible with STM32F103Cxxxx, i can put them on bluepill board . They are fast riscv.  Why not.

NB: by mistake i bought the ones with 64kB of flash :(

But there is a BIG showstopper, there seems to be no hw breakpoints, only sw breakpoints. 

If you have a lot of ram (like the RP2040) you can put the code in ram until it works fine and then put it in flash. That's not the case here.

Having the debugger read/modify/write all the time to but sw breakpoint in flash is really a pain.

In theory, the "flash" of the CH32 is actually flash copied to ram, so if there was a way to use the fake flash ram to put SW breakpoint in it, we would be good.

For reference, the CH32V303 has only 4 breakpoints, and no watchpoint (i.e. triggers with the right capabilities) which is already a bit of a pain in the neck.

I'll put those aside for the moment.


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