Dmac Activation - Renesas F-ZTAT H8 Series Hardware Manual

8.4.7

DMAC Activation

The DMAC can be activated by an internal interrupt, external request, or auto-request. The
available activation sources differ depending on the transfer mode and channel as indicated in
table 8.11.
Table 8.11 DMAC Activation Sources
Activation Source
Internal IMIA0
interrupts
IMIA1
IMIA2
IMIA3
TXI0
RXI0
External Falling edge of
DREQ
requests
Low input at
DREQ
Auto-request
Activation by Internal Interrupts: When an interrupt request is selected as a DMAC activation
source and the DTE bit is set to 1, that interrupt request is not sent to the CPU. It is not possible
for an interrupt request to activate the DMAC and simultaneously generate a CPU interrupt.
When the DMAC is activated by an interrupt request, the interrupt request flag is cleared
automatically. If the same interrupt is selected to activate two or more channels, the interrupt
request flag is cleared when the highest-priority channel is activated, but the transfer request is
held pending on the other channels in the DMAC, which are activated in their priority order.
Short Address Mode
Channels Channels
0A and 1A 0B and 1B
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
No Yes
No Yes
No No
Section 8 DMA Controller
Full Address Mode
Normal
No
No
No
No
No
No
Yes
Yes
Yes
Rev. 7.00 Sep 21, 2005 page 237 of 878
Block
Yes
Yes
Yes
Yes
No
No
Yes
No
No
REJ09B0259-0700