Datasheet

Rev.6.00 Oct.28.2004 page 172 of 1016
REJ09B0138-0600H
7.2.1 Memory Address Registers (MAR)
Bit :31302928272625242322212019181716
MAR :————————
Initial value : 0 0 0 00000********
R/W :————————R/WR/WR/WR/WR/WR/WR/WR/W
Bit :1514131211109876543210
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
*: Undefined
MAR is a 32-bit readable/writable register that specifies the transfer source address or destination address.
The upper 8 bits of MAR are reserved: they are always read as 0, and cannot be modified.
Whether MAR functions as the source address register or as the destination address register can be selected by means of
the DTDIR bit in DMACR.
MAR is incremented or decremented each time a byte or word transfer is executed, so that the address specified by MAR
is constantly updated. For details, see section 7.2.4, DMA Control Register (DMACR).
MAR is not initialized by a reset or in standby mode.
7.2.2 I/O Address Register (IOAR)
Bit :1514131211109876543210
IOAR :
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
*: Undefined
IOAR is a 16-bit readable/writable register that specifies the lower 16 bits of the transfer source address or destination
address. The upper 8 bits of the transfer address are automatically set to H'FF.
Whether IOAR functions as the source address register or as the destination address register can be selected by means of
the DTDIR bit in DMACR.
IOAR is invalid in single address mode.
IOAR is not incremented or decremented each time a transfer is executed, so that the address specified by IOAR is fixed.
IOAR is not initialized by a reset or in standby mode.