Chapter 31 External Bus
10.DMA Access Operation
■ 2-Cycle Transfer (I/O -> External)
Figure 10-10
"Timing Chart for 2-Cycle Transfer (I/O -> External)" shows the operation timing chart for (TYP3-
0=0000
, AWR=0008
B
H
Figure 10-10
"Timing Chart for 2-Cycle Transfer (I/O -> External)" shows a case in which a wait is not set for
memory and I/O.
MCLK
A[31:0]
AS
CSn
WRn
CSn
RD
D[31:0]
DACKn
FR30
compatible
mode
DEOPn
DACKn
Basic
mode
DEOPn
DREQn
•
The bus is accessed in the same way as an interface when the DMAC transfer is not performed.
•
In basic mode, DACKn/DEOPn is output both in the transfer source bus access and transfer destination bus
access.
10.8 2-Cycle Transfer (I/O -> SDRAM/FCRAM)
This section describes the operation of two - cycle transfer (I/O device to SDRAM/FCRAM).
604
, IOWR=00
).
H
Figure 10-10 Timing Chart for 2-Cycle Transfer (I/O -> External)
I/O address
idle
memory address