p2125vps20 Renesas Electronics Corporation., p2125vps20 Datasheet - Page 178

• Manufacturer Part Number: p2125vps20
• Description: 16-bit Single-chip Microcomputer H8s Family / H8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 7 Data Transfer Controller (DTC)
7.5.4
Setting the CHNE bit in MRB to 1 enables a number of data transfers to be performed
consecutively in response to a single transfer request. SAR, DAR, CRA, CRB, MRA, and MRB,
which define data transfers, can be set independently.
Figure 7.8 shows the overview of chain transfer operation. When activated, the DTC reads the
register information start address stored at the DTC vector address, and then reads the first register
information at that start address. After the data transfer, the CHNE bit will be tested. When it has
been set to 1, DTC reads the next register information located in a consecutive area and performs
the data transfer. These sequences are repeated until the CHNE bit is cleared to 0.
In the case of transfer with the CHNE bit set to 1, an interrupt request to the CPU is not generated
at the end of the specified number of transfers or by setting of the DISEL bit to 1, and the interrupt
source flag for the activation source is not affected.
Rev. 1.00 Sep. 21, 2006 Page 140 of 658
REJ09B0310-0100
DTC vector
address
Chain Transfer
Register information
start address
Figure 7.8 Chain Transfer Operation
Register information
Register information
CHNE = 1
CHNE = 0
Destination
Destination
Source
Source