HD64570 HITACHI [Hitachi Semiconductor], HD64570 Datasheet - Page 22

• Manufacturer Part Number: HD64570
• Description: Serial Communications Adaptor
• Manufacturer: HITACHI [Hitachi Semiconductor]

Rev. 0, 07/98, page 6 of 453
CPB (8)
decrementer (24)
Comparator (16)
DAR
BAR
SAR
Incrementer/
* Channels 0 and 2 only
Reserved
CDA (16)
EDA (16)
BFL
BCR (16)
(24)
(24)
Figure 1.3 DMAC Block Diagram (one channel)
(16)*
Address bus/data bus
DMA execution
control
DMR
DCR
DSR
FCT
DIR
Numbers in parentheses are
numbers of bits.
Bus control signals
Interrupt request signals
Single-address transfer control signal
(to MSCI)
DAR:
BAR:
SAR:
CPB:
CDA:
EDA:
BFL:
BCR:
FCT:
DSR:
DIR:
DMR:
DCR:
priority control
Request and
Destination address register
Buffer address register
Source address register
Chain pointer base
Current descriptor address register
Error descriptor address register
Receive buffer length
Byte count register
End-of-frame interrupt counter
DMA status register
DMA interrupt enable register
DMA mode register
DMA command register
DMA request
signal