Bus Control Words

The RP2040 and RP2350 support controlling bus priorities of CPU 0, CPU 1, DMA reads, and DMA writes. These bus priorities consist of a binary of either low priority or high priority. The words below enable setting and getting these priorities

busctrl

The busctrl module contains the following words:

high

( – priority )

High bus priority

low

( – priority )

Low bus priority

dma-w-bus-priority!

( priority – )

Set DMA write bus priority

dma-w-bus-priority@

( – priority )

Get DMA write bus priority

dma-r-bus-priority!

( priority – )

Set DMA read bus priority

dma-r-bus-priority@

( – priority )

Get DMA read bus priority

proc1-bus-priority!

( priority – )

Set CPU 1 bus priority

proc1-bus-priority@

( – priority )

Get CPU 1 bus priority

proc0-bus-priority!

( priority – )

Set CPU 0 bus priority

proc0-bus-priority@

( – priority )

Get CPU 0 bus priority