MPC555
/
MPC556
CENTRAL PROCESSING UNIT
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
3-53
• Multiple/string instructions
• Unaligned load/store instructions
In the last case, the store instruction can be partially completed if one of the accesses
(except the first one) causes the data storage protection error. The implementation-
specific data storage protection interrupt is taken in this case. For the update forms,
the update register (RA) is not altered.
3.15.5 Timer Facilities
Descriptions of the timebase and decrementer registers can be found in
SYSTEM CONFIGURATION AND PROTECTION
and in
3.15.6 Optional Facilities and Instructions
Any other
OEA
optional facilities and instructions (except those that are discussed
here) are not implemented by the MPC555 / MPC556
hardware. Attempting to execute
any of these instructions causes an implementation dependent software emulation in-
terrupt to be taken.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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