R01UH0823EJ0100 Rev.1.00
Page 341 of 1823
Jul 31, 2019
RX23W Group
18. DMA Controller (DMACA)
18.2.3
DMA Transfer Count Register (DMCRA)
Note:
Set the same value for DMCRAH and DMCRAL in repeat transfer mode and block transfer mode.
(1) Normal Transfer Mode (MD[1:0] Bits in DMACm.DMTMD = 00b)
DMCRAL functions as a 16-bit transfer counter.
The number of transfer operations is one when the setting is 0001h, and 65535 when it is FFFFh. The value is
decremented by one each time data is transferred.
When the setting is 0000h, no specific number of transfer operations is set; data transfer is performed with the transfer
counter stopped (free running mode).
DMCRAH is not used in normal transfer mode. Write 0000h to DMCRAH.
Address(es): DMAC0.DMCRA 0008 2008h, DMAC1.DMCRA 0008 2048h, DMAC2.DMCRA 0008 2088h, DMAC3.DMCRA 0008 20C8h
Normal transfer mode
DMCRAH
b31
b30
b29
b28
b27
b26
b25
b24
b23
b22
b21
b20
b19
b18
b17
b16
—
—
—
—
—
—
Value after reset:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
DMCRAL
b15
b14
b13
b12
b11
b10
b9
b8
b7
b6
b5
b4
b3
b2
b1
b0
Value after reset:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Repeat transfer mode, block transfer mode
DMCRAH
b31
b30
b29
b28
b27
b26
b25
b24
b23
b22
b21
b20
b19
b18
b17
b16
—
—
—
—
—
—
Value after reset:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
DMCRAL
b15
b14
b13
b12
b11
b10
b9
b8
b7
b6
b5
b4
b3
b2
b1
b0
0
0
0
0
0
0
Value after reset:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Symbol
Bit Name
Description
R/W
DMCRAL
Lower bits of transfer count
Specifies the number of transfer operations
R/W
DMCRAH
Upper bits of transfer count
R/W