Software Activation - Hitachi H8S/2378, H8S/2378R Series Hardware Manual

First data
transfer register
information
Second data
transfer register
information
9.7.4

Software Activation

An example is shown in which the DTC is used to transfer a block of 128 bytes of data by means
of software activation. The transfer source address is H'1000 and the destination address is
H'2000. The vector number is H'60, so the vector address is H'04C0.
1. Set MRA to incrementing source address (SM1 = 1, SM0 = 0), incrementing destination
address (DM1 = 1, DM0 = 0), block transfer mode (MD1 = 1, MD0 = 0), and byte size (Sz =
0). The DTS bit can have any value. Set MRB for one block transfer by one interrupt (CHNE =
0). Set the transfer source address (H'1000) in SAR, the destination address (H'2000) in DAR,
and 128 (H'8080) in CRA. Set 1 (H'0001) in CRB.
2. Set the start address of the register information at the DTC vector address (H'04C0).
3. Check that the SWDTE bit in DTVECR is 0. Check that there is currently no transfer activated
by software.
4. Write 1 to the SWDTE bit and the vector number (H'60) to DTVECR. The write data is H'E0.
Rev. 1.0, 09/01, page 400 of 904
Chain transfer
(counter = 0)
Figure 9.12 Chain Transfer when Counter = 0
Input circuit
Input buffer
Upper 8 bits
of DAR