2 ms·
I specified slave specifically because slave is a LOT harder. Master is always easy. Waiting for someone else’s clock and then capturing and replying asap is th
by dmitrygr 7mo ago
I specified slave specifically because slave is a LOT harder. Master is always easy. Waiting for someone else’s clock and then capturing and replying asap is the hard part. Especially if as a slave you need to simulate a read.
On rp2350 it is pio (wait for clock) -> pio (read address bus) -> dma (addr into lower bits of dma source for next channel) -> dma (Data from SRAM to PIO) -> pio (write data to data bus) chain and it barely keeps up.
- bunnie 7mo agoIf there's a single rising edge on the bus that you can use as quantum trigger, then, the reads turn into as series of moves into a FIFO, and the response can be quite fast. The quantum-trigger-on-GPIO was provided to solve exactly the problem you described.
- dmitrygr 7mo agoAwesome thank you.