r4f2456 Renesas Electronics Corporation., r4f2456 Datasheet - Page 426

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

Section 8 EXDMA Controller (EXDMAC)
(2)
Rev. 1.00 Sep. 19, 2008 Page 396 of 1342
REJ09B0467-0100
Bit
31 to 24
23 to 16
15 to 0
Block Transfer Mode
Bit Name
—
Initial Value
All 0
Undefined
Undefined
R/W
—
R/W
R/W
Description
Reserved
These bits are always read as 0 and cannot be
modified.
Block Size
These bits specify the block size (number of bytes
or number of words) for block transfer. Setting
H'01 specifies one as the block, while setting H'00
specifies the maximum block size, that is 256. The
register value always indicates the specified block
size.
16-Bit Transfer Counter
These bits specify the number of block transfers.
Setting H'0001 specifies one block transfer.
Setting H'0000 means no specification for the
number of transfers, and the transfer counter
function is halted. In this case, there is no transfer
end interrupt by the transfer counter. Setting
H'FFFF specifies the maximum number of block
transfers, that is 65,535. During EXDMA transfer,
this counter shows the remaining number of block
transfers.