Block Transfer Mode - Hitachi H8S/2378, H8S/2378R Series Hardware Manual

Normal mode setting
Set DMABCRH
Set transfer source and
transfer destination
addresses
Set number of transfers
Set DMACR
Read DMABCRL
Set DMABCRL
Normal mode
Figure 7.12 Example of Normal Mode Setting Procedure
7.5.7

Block Transfer Mode

In block transfer mode, data transfer is performed with channels A and B used in combination.
Block transfer mode can be specified by setting the FAE bit in DMABCRH and the BLKE bit in
DMACRA to 1. In block transfer mode, a data transfer of the specified block size is carried out in
response to a single transfer request, and this is executed for the number of times specified in
Rev. 1.0, 09/01, page 286 of 904
[1] Set each bit in DMABCRH.
• Set the FAE bit to 1 to select full address
mode.
• Specify enabling or disabling of internal
interrupt clearing with the DTA bit.
[1]
[2] Set the transfer source address in MARA, and
the transfer destination address in MARB.
[3] Set the number of transfers in ETCRA.
[4] Set each bit in DMACRA and DMACRB.
[2]
• Set the transfer data size with the DTSZ bit.
• Specify whether MARA is to be incremented,
decremented, or fixed, with the SAID and
SAIDE bits.
[3]
• Clear the BLKE bit to 0 to select normal
mode.
• Specify whether MARB is to be incremented,
decremented, or fixed, with the DAID and
DAIDE bits.
[4]
• Select the activation source with bits DTF3 to
DTF0.
[5] Read DTE = 0 and DTME = 0 in DMABCRL.
[5]
[6] Set each bit in DMABCRL.
• Specify enabling or disabling of transfer end
interrupts with the DTIE bit.
• Set both the DTME bit and the DTE bit to 1 to
enable transfer.
[6]