User manual

8-20
DMACTL1, DMA Control Register 1
15 14 13 12 11 10 9 8
0
0 0 0 0 0 0 0
r0 r0 r0 r0 r0 r0 r0 r0
76543210
0 0 0 0 0
DMA
ONFETCH
ROUND
ROBIN
ENNMI
r0 r0 r0 r0 r0 rw−(0) rw−(0) rw−(0)
Reserved
Bits
15−3
Reserved. Read only. Always read as 0.
DMA
ONFETCH
Bit 2 DMA on fetch
0 The DMA transfer occurs immediately
1 The DMA transfer occurs on next instruction fetch after the trigger
ROUND
ROBIN
Bit 1 Round robin. This bit enables the round-robin DMA channel priorities.
0 DMA channel priority is DMA0 − DMA1 − DMA2
1 DMA channel priority changes with each transfer
ENNMI
Bit 0 Enable NMI. This bit enables the interruption of a DMA transfer by an NMI
interrupt. When an NMI interrupts a DMA transfer, the current transfer is
completed normally, further transfers are stopped, and DMAABORT is set.
0 NMI interrupt does not interrupt DMA transfer
1 NMI interrupt interrupts a DMA transfer