MPC555
/
MPC556
MEMORY CONTROLLER
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
10-23
Figure 10-17 Aliasing Phenomena Illustration
The default state is to allow dual-mapping data accesses only; this means that dual
mapping is possible only for data accesses on the internal bus. Also, the default state
takes the lower two Mbytes of the MPC555 / MPC556 internal flash memory. Hence,
caution should be taken to change the dual-mapping setup before the first data ac-
cess.
NOTE
Dual mapping is
not
supported for an external master when the mem-
ory controller serves the access; In such a case, the MPC555 /
MPC556 terminates the cycle by asserting TEA.
MPC555
/
MPC556 Memory Map
CSx
Physical External Memory
External CSx
Flash
Dual Mapping
Dual-Map region
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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