R01UH0823EJ0100 Rev.1.00
Page 397 of 1823
Jul 31, 2019
RX23W Group
19. Data Transfer Controller (DTCa)
19.4.5
Block Transfer Mode
This mode allows single-block data transfer on a single transfer request.
Specify either transfer source or transfer destination for the block area by the MRB.DTS bit. The block size can be set to
1 to 256 bytes, 1 to 256 words, or 1 to 256 longwords.
When transfer of the specified one block is completed, the initial values of the block size counter CRAL and the address
register (the SAR register when the MRB.DTS bit is 1 or the DAR register when the DTS bit is 0) specified in the block
area are restored. The other address register is incremented or decremented continuously or remains unchanged.
The transfer count (block count) can be set to 1 to 65536. This mode enables an interrupt request to the CPU to be
generated at the end of specified-count block transfer.
lists register functions in block transfer mode, and
shows the memory map of block transfer
mode.
Note 1. Write-back operation is skipped when address is fixed.
Figure 19.7
Memory Map of Block Transfer Mode (Transfer Destination: Block Area)
Table 19.7
Register Functions in Block Transfer Mode
Register
Description
Value Written Back by Writing Transfer Information
When MRB.DTS Bit is 0
When MRB.DTS Bit is 1
SAR
Transfer source address
Increment/decrement/fixed*
SAR register initial value
DAR
Transfer destination address
DAR register initial value
Increment/decrement/fixed*
Retains initial value of block size
Block size counter
CRB
Block transfer counter
CRB – 1
Transfer source data area
Transfer destination data area
(set to block area)
Block area
DAR
SAR
Transfer
nth block
First block