Resolved! Wait for HSI/PLL/Sysclk etc etc ready - Why???
I am new to Arm but old to assembly coding (inc Toshiba 32 bit CISC - now extinct).. Just completed RCC startup code for a STM32F344 chip by looking at the 1124 pages (!) of the RM0364 manual and the CUBE LL start up code (!!!). The CUBE code has wai...