BAT32G1x9 user manual | Chapter 24 Enhanced DMA
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Rev.1.02
Chapter 24 Enhanced DMA
24.1 Features of the DMA
DMA is the function of transferring data between memories without using the CPU. Start the DMA for
data transfer via peripheral interrupts. When the DMA and CPU access the same unit in flash, SRAM0,
SRAM1, or peripheral modules at the same time, their bus usage is higher than the CPU. When the DMA
and CPU access flash, SRAM0, SRAM1, or different units in the peripheral module, respectively, the two
do not interfere with each other and can be executed in parallel.
The specifications of the DMA are shown in Table 24-1.
Table 24-1
Specifications of the DMA (1/2).
Item
specification
Startup Source
Up to 40 startup sources
Assignable control data
40 groups
The address
space that
can be
transmitted
Address space
Full address range space
source
Full address range space is optional
target
Full address range space is optional
Maximum
number of
transfers
Normal mode
65535 times
Repeat pattern
65535 times
The maximum
transfer block
size
Normal mode
(8-bit transmission).
65535 bytes
Normal mode
(16-bit transmission).
131070 bytes
Normal mode
(32-bit transmission).
262140 bytes
Repeat pattern
65535 bytes
Teleportation units
8-bit/16-bit/32-bit
Transfer mode
Normal mode
Ends after a transfer of the DMACTj register from "1" to "0".
Repeat pattern
After the transfer of the DMCTj register from "1" to "0" is completed, the
address of the duplicate region is initialized, and the DMRLDj is changed
The value of the register continues after reloading into the DMCTj register.
Address control
Normal mode
Fixed or incremented
Repeat pattern
Fixed or incremented the address of the distinct area.
The priority of the startup source
Refer to "Table 24-5 DMA startup source and vector addresses".