9 SRAM CONTROLLER (SRAMC)
S1C33L26 TECHNICAL MANUAL
Seiko Epson Corporation
9-9
SRAM Read/Write Timings with External #WAIT
9.6.2
Wait cycles can be inserted from the #WAIT pin only for SRAM-type devices.
The external #WAIT signal is sampled on the rising edges of BCLK after the #CE setup cycles end and no later
than one clock before the read or write signal goes high. A wait state is entered while the #WAIT signal is sampled
active (low), and subsequent operation resumes when the #WAIT signal is sampled inactive (high).
[Example settings]
Device size:
16 bits
Number of static wait cycles: 0 cycles (see Note below)
#CE setup/hold time:
1 cycle (see Note below)
CLK
A[25:0]
#CE
x
#RD
D[15:0]
#WAIT
valid
valid
Wait cycle
6.2.1 SRAM Read Timing with External #WAIT
Figure 9.
CLK
A[25:0]
#CE
x
#WR
*
D[15:0]
#WAIT
valid
valid
Wait cycle
6.2.2 SRAM Write Timing with External #WAIT
Figure 9.