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Rev. 2.0, 09/02, page 153 of 732
10.3.3
DMA Transfer Count Registers_0 to 3 (DMATCR_0 to DMATCR_3)
DMA transfer count registers_0 to 3 (DMATCR_0 to DMATCR_3) are 32-bit readable/writable
registers that specify the transfer count for each channel (byte count, word count, or longword
count) with lower 24 bits. Specifying a H'000001 gives a transfer count of 1, while H'000000
gives the maximum setting, 16,777,216 transfers. While DMAC is in operation, the number of
transfers to be performed is indicated. Upper eight bits of this register are read as 0s and should
always be written with 0s.When this register is accessed in 16 bits, the value of another 16 bits
that are not accessed is retained.
The initial value of DMATCR is undefined.
10.3.4
DMA Channel Control Registers_0 to 3 (CHCR_0 to CHCR_3)
DMA channel control registers_0 to 3 (CHCR_0 to CHCR_3) is a 32-bit readable/writable register
where the operation and transmission of each channel is designated.
Bit
Bit Name
Initial Value
R/W
Description
31
30
29
28
27
26
25
24
23
22
21
DI
0
0
0
0
0
0
0
0
0
0
0
R
R
R
R
R
R
R
R
R
R
R
Reserved
These bits are read as 0s and should always be
written with 0s.
20
0
(R/W)
*
2
Direct/Indirect
Specifies either direct address mode operation or
indirect address mode operation for channel 3
source address. This bit is valid only in CHCR_3.
For CHCR0 to CHCR2, this bit is always read as 0
and should always be written with 0.
0: Direct access mode operation for channel 3
1: Indirect access mode operation for channel 3
19
RO
0
(R/W)
*
2
Source Address Reload
Selects whether to reload the source address initial
value during channel 2 transfer. This bit is valid only
for channel 2. For CHCR_0, 1 ,3, this bit is always
read as 0 and should always be written with 0.
0: Does not reload source address
1: Reloads source address