HD6417705F133V Datasheet, PDF (305/741 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7700 Series

8.4.3 Channel Priority
When the DMAC receives simultaneous transfer requests on two or more channels, it selects a
channel according to a predetermined priority order. Two modes (fixed mode and round-robin
mode) are selected by bits PR1 and PR0 in the DMA operation register (DMAOR).
Fixed Mode: In these modes, the priority levels among the channels remain fixed. There are two
kinds of fixed modes as follows:
CH0 > CH1 > CH2 > CH3
CH0 > CH2 > CH3 > CH1
These are selected by the PR1 and the PR0 bits in the DMA operation register (DMAOR).
Rev. 2.00, 09/03, page 257 of 690