
Functional Description and Application Information
Computer Operating Properly (S12SCOPV1)
MM912F634
Freescale Semiconductor
265
4.35.3.2.1
COP Control Register (COPCTL)
This register controls the COP (Computer Operating Properly) watchdog.
Read: Anytime
Write:
1.
RSBCK: anytime in special modes; write to “1” but not to “0” in all other modes
2.
WCOP, CR2, CR1, CR0:
— Anytime in special modes
— Write once in all other modes
– Writing CR[2:0] to “000” has no effect, but counts for the “write once” condition.
– Writing WCOP to “0” has no effect, but counts for the “write once” condition.
The COP timeout period is restarted if one these two conditions are true:
1.
Writing a non-zero value to CR[2:0] (anytime in special modes, once in all other modes) with WRTMASK = 0.
or
2.
Changing RSBCK bit from “0” to “1”.
Table 342. COP Control Register (COPCTL)
0x003E
7
6
5
432
10
R
WCOP
RSBCK
0
COPSWAI
COPRSTP
CR2
CR1
CR0
W
WRTMASK
see note
0
see note
Note:
Table 343. COPCTL Field Descriptions
Field
Description
7
WCOP
Window COP Mode Bit — When set, a write to the ARMCOP register must occur in the last 25% of the selected period. A
write during the first 75% of the selected period will reset the part. As long as all writes occur during this window, $55 can be
written as often as desired. Once $AA is written after the $55, the timeout logic restarts and the user must wait until the next
window before writing to ARMCOP.
Table 344 shows the duration of this window for the seven available COP rates.
0 Normal COP operation
1 Window COP operation
6
RSBCK
COP and RTI Stop in Active BDM Mode Bit
0 Allows the COP and RTI to keep running in Active BDM mode.
1 Stops the COP and RTI counters whenever the part is in Active BDM mode.
5
WRTMASK
Write Mask for WCOP and CR[2:0] Bit — This write-only bit serves as a mask for the WCOP, CR[2:0], COPSWAI and
COPRSTP bits while writing the COPCTL register. It is intended for BDM writing the RSBCK without touching the contents of
WCOP, CR[2:0], COPSWAI, and COPRSTP.
0 Write of WCOP, CR[2:0], COPSWAI and COPRSTP has an effect with this write of COPCTL
1 Write of WCOP, CR[2:0], COPSWAI and COPRSTP has no effect with this write of COPCTL.
(Does not count for “write once”)
4
COPSWAI
COP Stops in Wait mode bit
Normal modes: Write once
Special modes: Write anytime
0 COP continues in Wait mode.
1 COP stops and initializes the COP counter whenever the part enters Wait mode.