Register Descriptions (2) (Full Address Mode); Memory Address Register (Mar); I/O Address Register (Ioar); Execute Transfer Count Register (Etcr) - Renesas H8S Series Hardware Manual

7.3

Register Descriptions (2) (Full Address Mode)

Full address mode transfer is performed with channels A and B together. For details of full address mode setting, see table
7-4.
7.3.1

Memory Address Register (MAR)

Bit : 31 30
MAR : — —
Initial value : 0 0
R/W : — —
Bit : 15 14
MAR :
Initial value :
* *
R/W : R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W R/W
MAR is a 32-bit readable/writable register; MARA functions as the transfer source address register, and MARB as the
destination address register.
MAR is composed of two 16-bit registers, MARH and MARL. The upper 8 bits of MARH are reserved; they are always
read as 0, and cannot be modified.
MAR is incremented or decremented each time a byte or word transfer is executed, so that the source or destination
memory address can be updated automatically. For details, see section 7.3.4, DMA Control Register (DMACR).
MAR is not initialized by a reset or in standby mode.
7.3.2

I/O Address Register (IOAR)

IOAR is not used in full address transfer.
7.3.3

Execute Transfer Count Register (ETCR)

ETCR is a 16-bit readable/writable register that specifies the number of transfers. The function of this register is different
in normal mode and in block transfer mode.
ETCR is not initialized by a reset or in standby mode.
29 28 27 26 25
— — — — —
0 0 0 0 0
— — — — —
13 12 11 10 9
* * * * *
24 23 22 21 20
—
0 * * * *
— R/W R/W R/W R/W R/W R/W R/W R/W
8 7 6 5 4
* * * * *
19 18 17 16
* * * *
3 2 1 0
* * * *
Rev.6.00 Oct.28.2004 page 181 of 1016
REJ09B0138-0600H
*: Undefined