r4f2456 Renesas Electronics Corporation., r4f2456 Datasheet - Page 389

• Manufacturer Part Number: r4f2456
• Description: 16-bit Single-chip Microcomputer H8s Family / H8s/2400 Series
• Manufacturer: Renesas Electronics Corporation.

ETCRAL is decremented by 1 each time a byte or word transfer is performed. In response to a
single transfer request, burst transfer is performed until the value in ETCRAL reaches H'00.
ETCRAL is then loaded with the value in ETCRAH. At this time, the value in the MAR register
for which a block designation has been given by the BLKDIR bit in DMACRA is restored in
accordance with the DTSZ, SAID/DAID, and SAIDE/DAIDE bits in DMACR.
Address T
Address B
Legend:
Address
Address
Address
Address
Where :
A
A
T
T
B
B
L
L
N
M
A
B
A
B
A
B
= L
= L
= L
= L
= Value set in MARA
= Value set in MARB
= Value set in ETCRB
= Value set in ETCRAH and ETCRAL
Figure 7.14 Operation in Block Transfer Mode (BLKDIR = 1)
A
B
A
B
+ SAIDE · (–1)
+ DAIDE · (–1)
Block area
SAID
DAID
· (2
· (2
DTSZ
DTSZ
Consecutive transfer
of M bytes or words
is performed in
response to one
request
· (N – 1))
· (M·N – 1))
Transfer
Rev. 1.00 Sep. 19, 2008 Page 359 of 1342
2nd block
1st block
Nth block
Section 7 DMA Controller (DMAC)
REJ09B0467-0100
Address T
Address B
B
B