Datasheet

Registers and Reset Initialization
MC68HC812A4 Data Sheet, Rev. 7
Freescale Semiconductor 109
10.5.4 Arm/Reset COP Timer Register
To restart the COP timeout period and avoid a COP reset, write $55 and then $AA to this address before
the end of the COP timeout period. Other instructions can be executed between these writes. Writing
anything other than $55 or $AA causes a COP reset to occur.
Address: $0017
Bit 7654321Bit 0
Read:00000000
Write: Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Reset:00000000
Figure 10-10. Arm/Reset COP Timer Register (COPRST)