I have that version running using the DMA interface.
Putting a scope on the ~OE pin of the data bus level converter is a useful way of measuring/comparing the timings. It transitions to low when the pico is ready to read/write to the data bus - and transitions to high at the end of the clock cycle.
BEFORE (using the CPU)![:(]( "Sad")
AFTER (using DMA) ![:D]( "Very Happy")
Test conditions:
- 2MHz operation
- both versions wait for mid-cycle to start reading the address bus
- the assembler test program reads from then writes to #BDE0 in a loop
Putting a scope on the ~OE pin of the data bus level converter is a useful way of measuring/comparing the timings. It transitions to low when the pico is ready to read/write to the data bus - and transitions to high at the end of the clock cycle.
BEFORE (using the CPU)
AFTER (using DMA) 
Test conditions:- 2MHz operation
- both versions wait for mid-cycle to start reading the address bus
- the assembler test program reads from then writes to #BDE0 in a loop
Statistics: Posted by cjm — Mon Oct 14, 2024 11:11 pm