SH7641 Datasheet, PDF (466/1036 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH™ RISC engine Family / SH7641 Series

Section 13 Direct Memory Access Controller (DMAC)
13.3.5 DMA Operation Register (DMAOR)
The DMA operation register (DMAOR) is a 32-bit read/write register that specifies the priority
level of channels at the DMA transfer. This register shows the DMA transfer status. The DMAOR
is initialized to H'00000000 at reset and retains the current value in the standby or module standby
mode.
Bit
31, 30
29
28
27, 26
Bit Name

CMS1
CMS0

Initial
Value
All 0
0
0
All 0
R/W Description
R
Reserved
These bits are always read as 0. The write value
should always be 0.
R/W Cycle Steal Mode Select 1, 0
R/W These bits select either normal mode or intermittent
mode in cycle steal mode.
It is necessary that the bus modes of all channels be
set to cycle steal mode to make the intermittent mode
valid.
00: Normal mode
01: Reserved (Setting prohibited)
10: Intermittent mode 16
Executes one DMA transfer in each of 16 clocks of
an external bus clock.
11: Intermittent mode 64
Executes one DMA transfer in each of 64 clocks of
an external bus clock.
R
Reserved
These bits are always read as 0. The write value
should always be 0.
Rev. 4.00 Sep. 14, 2005 Page 416 of 982
REJ09B0023-0400