Chain Transfer; Figure 8.8 Chain Transfer Operation - Hitachi H8S/2628 Hardware Manual

H8s/2628 series 16-bit single-chip microcomputer
Table of Contents

Advertisement

8.5.4

Chain Transfer

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 8.8 shows the outline of the chain transfer operation.
When activated, the DTC reads the register information start address stored at the vector address
corresponding to the activation source, and then reads the first register information at that start
address. After data transfer ends, 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 CHNE 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.
Register information
DTC vector
address
Rev. 1.0, 09/02, page 112 of 568
start address

Figure 8.8 Chain Transfer Operation

Register information
CHNE=1
Register information
CHNE=0
Source
Destination
Source
Destination

Advertisement

Table of Contents
loading

This manual is also suitable for:

Hd64f2628Hd6432628H8s/2627Hd6432627

Table of Contents