UPD70208HGF-16-3B9 NEC, UPD70208HGF-16-3B9 Datasheet - Page 33

• Manufacturer Part Number: UPD70208HGF-16-3B9
• Description: V40HLTM/ V50HLTM 16/8/ 16-BIT MICROPROCESSOR
• Manufacturer: NEC

Internal Address Bus
External
pins
12. DMAU (DMA CONTROL UNIT)
12.1 FEATURES
12.2 DMAU INTERNAL BLOCK DIAGRAM
Internal Control Bus
Internal Data Bus
The DMAU has 4 DMA channels, and provides the functions (subset) of two LSIs, the PD71071 and PD71037.
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Notes 1. In PD71071 mode
BAU
Two operating modes ( PD71071 mode, PD71037 mode)
20-bit address register
16-bit count register
Four independent DMA channels
Byte transfer/word transfer selectable
Three transfer modes (settable on an individual channel basis)
Two bus modes (common to all channels: in PD71037 mode, bus release mode only)
DMA requests maskable on an individual channel basis
Auto initialization function
Transfer address increment/decrement
Two channel priority systems (fixed priority/rotating priority)
TC output at end of transfer
Forced termination of service by END input
Cascading capability
DMARQ0-
DMARQ3
DMAAK0-
DMAAK3
Single transfer mode, demand transfer mode, block transfer mode
Bus release mode
Bus hold mode
END/TC
BUSRQ
2. In PD71037 mode
BUSAK
(20)
(8)
Priority Control
Internal Bus
Interface
DMAU Address Bus (20)
Data Sheet U13225EJ4V0DS00
Terminal Count
Registers
Count
Registers
Address
DMAU Data Bus
Current Address (20
Base Address (20
Base Count (16
Current Count (16
Address Increment/
Count Decrementer
Decrement
(20)
(16)
4)
4)
4)
4)
PD70208H, 70216H
Control Register Group
Channel
Device Control
Status
Mode Control
Mask
Request
Note 1
Note 2
(7
(10)
(4)
(8)
(4)
(4)
4)
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