r4f2456 Renesas Electronics Corporation., r4f2456 Datasheet - Page 381

• Manufacturer Part Number: r4f2456
• Description: 16-bit Single-chip Microcomputer H8s Family / H8s/2400 Series
• Manufacturer: Renesas Electronics Corporation.

7.5.5
Single address mode can only be specified for channel B. This mode can be specified by setting
the SAE bit in DMABCRH to 1 in short address mode.
One address is specified by MAR, and the other is set automatically to the data transfer
acknowledge pin (DACK). The transfer direction can be specified by the DTDIR bit in DMACR.
Table 7.8 summarizes register functions in single address mode.
Table 7.8
MAR specifies the start address of the transfer source or transfer destination as 24 bits. IOAR is
invalid; in its place the strobe for external devices (DACK) is output.
Figure 7.9 illustrates operation in single address mode (when sequential mode is specified).
Register
23
15
Single Address Mode
DACK pin
Register Functions in Single Address Mode
ETCR
MAR
0
0
DTDIR = 0 DTDIR = 1 Initial Setting
Source
address
register
Write
strobe
Transfer counter
Function
Destination
address
register
Read
strobe
Start address of
transfer destination
or transfer source
(Set automatically
by SAE bit in
DMABCRH; IOAR
is invalid)
Number of transfers See sections 7.5.2,
Rev. 1.00 Sep. 19, 2008 Page 351 of 1342
Section 7 DMA Controller (DMAC)
Operation
See sections 7.5.2,
Sequential Mode,
7.5.3, Idle Mode,
and 7.5.4, Repeat
Mode.
Strobe for external
device
Sequential Mode,
7.5.3, Idle Mode,
and 7.5.4, Repeat
Mode.
REJ09B0467-0100