IBT Technologies IB798, User Manual

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INSTALLATIONS
22 IB798 User’s Manual
I/O Command
Relays are "Dis-energized"
Driver
Relay
WDT
Bypass State
Ethemet#2
Ethemet#1
Bypass
RJ45
Relays
RJ45 CN2
CN3
Status LED Programming
Programming the status LED can be done with the I/O port 404Dh bit7.
When I/O port 404Dh bit 7 is set as 0 (low), then the LED is not active.
When I/O port 404Dh bit 7 is set as 1 (high), then the LED is active.
Enable / Disable Bypass Mode
The I/O port 0442H can be defined to select between normal and bypass
modes. The following describes the programming procedure.
Enabling Watchdog (Bypass mode):
MOV AX, 000F
MOV DX, 0442H
OUT DX, AX
Disabling Watchdog (Normal Mode):
MOV AX, 0010
MOV DX, 0442H
OUT
DX, AX