Synchronous Write Enable Output - Fujitsu FR60 Hardware Manual

CHAPTER 4 EXTERNAL BUS INTERFACE
4.5.7

Synchronous Write Enable Output

This section shows the operation timing for synchronous write enable output.
■ Operation Timing for Synchronous Write Enable Output
Figure 4.5-7 shows the operation timing for (TYP3 to TYP0=0000
Figure 4.5-7 Timing Chart for Synchronous Write Enable Output
MCLK
A31 to A00
AS
CSn
RD
Read
D31 to D00
WRn
Write
D31 to D00
If synchronous write enable output is enabled (If the W03 bit of the AWR is "1"), operation is as
follows.
• WR0 to WR3 and WR pin output asserts synchronous write enable output at the timing at
which AS pin output is asserted. For a write to an external bus, the synchronous write enable
output is "L". For a read from an external bus, the synchronous write enable output is "H".
• Write data is output from the external data output pin in the clock cycle following the cycle in
which synchronous write enable output is asserted.
• Read strobe output (RD) functions as an asynchronous read strobe regardless of the setting
of WR0 to WR3 and WR output timing. Use it as is for controlling the data I/O.
210
, AWR=0000 ).
B H