Reset Fault Or Alarm - 0X51 - Honeywell CM4 Technical Handbook

CM4 Four-Point Continuous Monitor

Reset Fault or Alarm - 0x51

This command allows a remote reset of any faults or alarm
conditions.
Command packet to instrument:
Command Code (0x51) - 1 byte
Flag - 1 byte
bits 0-4: Reset selection
0x01 = Point 1 alarms
0x02 = Point 2 alarms
0x04 = Point 3 alarms
0x08 = Point 4 alarms
0x10 = Faults
Response packet from instrument:
Command Code (0x51) - 1 byte
CM4 Date - 2 bytes
CM4 Time - 2 bytes
Status - 1 byte
0x00 = Alarms reset
0xff = Error
CM4 Technical Manual
Set Key-Code - 0x52
This command allows you to reconfigure the keypad lock-out and
key code. The keypad can be disabled, preventing unauthorized user
intervention by enabling the keypad lockout (bit 0). This configures the
keypad and a new key code.
The old key code must match the code currently programmed into the
CM4 monitor for this command to succeed in changing the code.
Command packet to instrument:
Command Code (0x51) - 1 byte
Keypad Status - 1 byte
bit 0: Keypad lock-out function
0 = Disable
1 = Enable
bits 1-7: Undefined
Old Key code - 2 bytes (valid 0000 - 9999)
New Key code - 2 bytes (valid 0000-9999)
Response packet from instrument:
Command Code (0x51) - 1 byte
CM4 Date - 2 bytes
CM4 Time - 2 bytes
Status -1 byte
0x00 = Saved and verified
0x01 = Key code invalid
0xff = Error, not saved
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