MPC555
/
MPC556
MEMORY CONTROLLER
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
10-13
In
, note the following:
• Because the TRLX bit is set, the assertion of the CS and WE strobes is delayed
by one clock cycle.
• Because ACS = 11, the assertion of CS is delayed an additional half clock cycle.
• Because CSNT = 1, WE is negated one clock cycle earlier than normal. (Refer to
). The total cycle length is four clock cycles, determined as follows:
— The basic memory cycle requires two clock cycles.
— Two extra clock cycles are required due to the effect of TRLX on the assertion
and negation of the CS and WE strobes.
Figure 10-11 Relaxed Timing – Write Access
(ACS = 11, SCY = 0, CSNT = 1, TRLX = 1)
Clock
Address
TS
TA
CS
RD/WR
WE/BE
Data
OE
ACS =11
ACS!=00 & CSNT = 1
CSNT = 1
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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