HD6473032F16 Datasheet, PDF (254/847 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

Section 8 DMA Controller
Figure 8.12 shows a sample setup procedure for block transfer mode.
Block transfer mode
Set source address
1
Set destination address
2
Set block transfer count 3
Set block size
4
Set DTCRB (1)
5
Set DTCRA (1)
6
Read DTCRB
7
Set DTCRB (2)
8
Read DTCRA
9
1. Set the source address in MARA.
2. Set the destination address in MARB.
3. Set the block transfer count in ETCRB.
4. Set the block size (number of bytes or words) in
both ETCRAH and ETCRAL.
5. Set the DTCRB bits as follows.
• Clear the DTME bit to 0.
• Set the DAID and DAIDE bits to select whether
MARB is incremented, decremented, or held
fixed.
• Set or clear the TMS bit to make the block area
the source or destination.
• Select the DMAC activation source with bits
DTS2B to DTS0B.
6. Set the DTCRA bits as follows.
• Clear the DTE to 0.
• Select byte size or word size with the DTSZ bit.
• Set the SAID and SAIDE bits to select whether
MARA is incremented, decremented, or held
fixed.
• Set or clear the DTIE bit to enable or disable
the CPU interrupt at the end of the transfer.
• Set bits DTS2A to DTS0A all to 1 to select
block transfer mode.
7. Read DTCRB with DTME cleared to 0.
8. Set the DTME bit to 1 in DTCRB.
9. Read DTCRA with DTE cleared to 0.
10. Set the DTE bit to 1 in DTCRA to enable the
transfer.
Set DTCRA (2)
10
Block transfer mode
Note: Carry out settings 1 to 10 with the DEND interrupt masked in the CPU.
If an NMI interrupt occurs during the setup procedure, it may clear the DTME bit to 0, in
which case the transfer will not start.
Figure 8.12 Block Transfer Mode Setup Procedure (Example)
Rev. 3.00 Mar 21, 2006 page 224 of 814
REJ09B0302-0300