S9S12G48F1CLC Datasheet, PDF (415/1292 Pages) Freescale Semiconductor, Inc – Microcontrollers

S12 Clock, Reset and Power Management Unit (S12CPMU)
COP is written at the correct time (due to independent API interrupt request) but the wrong value is written
(alternating sequence of $55 and $AA is no longer maintained) which causes a COP reset.
MC9S12G Family Reference Manual, Rev.1.23
Freescale Semiconductor
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