MPC555
/
MPC556
MEMORY CONTROLLER
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
10-9
Figure 10-7 Peripheral Devices Interface
The
CSx timing is defined by the setup time required between the address lines and
the CE line. The memory controller allows the user to specify the CS timing to meet
the setup time required by the peripheral device. This is accomplished through the
ACS
field in the base register. In
, the ACS bits are set to 11, so CSx is
asserted half a clock cycle after the address lines are valid.
Figure 10-8 Peripheral Devices Basic Timing
(ACS = 11,TRLX = 0)
Peripheral
Address
CE
R/W
Data
Address
CSx
RD/WR
Data
MPC555 / MPC556
CLOCK
Address
TS
TA
CS
RD/WR
Data
ACS = 11
CSNT = 1
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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