I wish the connections were 1-1 so a straight ribbon cable would have worked, but it needs a slight re-pinout. This is what I did after reviewing the core, sid and core32 schematics (and the unofficial_sid_v4 from luke).
STM32/J19 pin name = SID Module pin name
RC1 = RCLK
RC2 = CS#
SC = SCLK
SO = MU (or SER)
SI = CLK
5V = 5V
VSS = VSS
It worked the first time. I got 1kHz from my SID 6581. Horraayyyy
Next step is to figure out how to play SID files from either SIDPLAYER or from a SDCARD hooked up to the STM32.
the latter shouldn't be that difficult, right? (am I dreaming?) I found a piece of code searching either this forum or other, that outputs SID register writes while processing a SID file. (siddump at http://covertbitops.c64.org/). If we can port this code to stm32 and let it dump the files into the sid directly, it should work?
Great job to TK and others btw, stm32 & tols are great.