HD6473032F16 Datasheet, PDF (223/847 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

Section 8 DMA Controller
8.2.2 I/O Address Registers (IOAR)
An I/O address register (IOAR) is an 8-bit readable/writable register that specifies a source or
destination address. The IOAR value is the lower 8 bits of the address. The upper 16 address bits
are all 1 (H'FFFF).
Bit
7
6
5
4
3
2
1
0
Initial value
Read/Write
Undetermined
R/W
R/W R/W
R/W
R/W
R/W
R/W
R/W
Source or destination address
An IOAR functions as a source or destination address register depending on how the DMAC is
activated: as a source address register if activation is by a receive-data-full interrupt from the SCI
(channel 0), and as a destination address register otherwise.
The IOAR value is held fixed. It is not incremented or decremented when a transfer is executed.
The IOARs are not initialized by a reset or in standby mode.
Rev. 3.00 Mar 21, 2006 page 193 of 814
REJ09B0302-0300