HD6417660 RENESAS [Renesas Technology Corp], HD6417660 Datasheet - Page 362

• Manufacturer Part Number: HD6417660
• Description: Renesas 32-Bit RISC Microcomputer
• Manufacturer: RENESAS [Renesas Technology Corp]

Figures 10.8 shows an example of DMA transfer timing in single address mode.
Rev. 1.00, 02/04, page 324 of 804
Two kinds of transfer are possible in single address mode: (1) transfer between an external
device with DACK and a memory-mapped external device, and (2) transfer between an
external device with DACK and external memory. In both cases, only the external request
signal (DREQ) is used for transfer requests.
D15 to D0
D15 to D0
A23 to A0
A23 to A0
Figure 10.8 Example of DMA Transfer Timing in Single Address Mode
DACK
DACK
CKIO
CKIO
CSn
CSn
WE
RD
This LSI
(b) External memory space (ordinary memory) → external device with DACK
(a) External device with DACK → external memory space (ordinary memory)
Figure 10.7 Data Flow in Single Address Mode
Data flow
DMAC
External address bus
DACK
DREQ
Address output to external memory space
Select signal to external memory space
Write strobe signal to external memory space
Data output from external device with DACK
DACK signal (active-low) to external device with DACK
Address output to external memory space
Select signal to external memory space
Read strobe signal to external memory space
Data output from external memory space
DACK signal (active-low) to external device with DACK
External data bus
External device
with DACK
External
memory