7i77 watch dog catch 22

Question 1:
Is there an output pin for an external Estop/reset safety circuit to read the status of 7i77 WDT? If not, would it be feasible to use one of the existing pin outputs by Keeping this output pin ON while the watchdog timer has NOT bit. Here where the catch 22 comes into play, when the WDT bites, the hostmot2 driver disables the digital outputs therefore my external hardwired circuit will not be able to determine the WDT output pin status (see diagram Highlighted in RED). One way I can think of to solve this puzzle is to restrict the WDT from internally disabling the digital outputs, and have WDT just set a flag and let the hardwired safety circuit take care of disabling the power to the digital outputs.       Or I am out to lunch?Question 2:
7i77 field terminal block has several terminals I am hoping to be able to keep the field power OFF to the digital outputs until the safety lockout circuit is reset and the field digital inputs and VIN powered while the ESTOP circuit is active. If you look at the wiring diagram, I need the numbers of the terminal blocks marked with question mark (highlited in green). Nomenclature:
CR# – CONTROL RELAY
MCR - MASTER CONTROL RELAY
F# - FUSE
DI – DIGITAL INPUT
DO – DIGITAL OUTPUT
PB – PUSH BUTTON
WDT – WATCH DOG TIMER
L1 - MAIN SUPPLY LINE 120 VAC
N - MAIN SUPPLY NEUTRAL
PL- Pilot Light A brief explanation to what this hardwired circuit does follows this diagram.
  The wiring circuit diagram below  is a hardwired circuit that will allow power to be removed from digital outputs, servos and spindle. The circuit achieves the following:

• If power is lost during operation the machine will not restart when power is re-established.
• If an Estop is activated or a fault occurs during operation, the circuit will inhibit (prevent) power to digital outputs, servos and spindle. The rest of the machine control circuit will stay in the ON state; this will enable you to troubleshoot and resume operation without major reinitialization of the machine.
• Machine will not restart until all faults are corrected and operator presses reset button.

This hardwired circuit is the equivalent of safety relay without guided contacts.

A 7I77 watchdog fault occurs when communication with LinuxCNC is lost.
This is not something you typically recover from without restarting
LinuxCNC, that is, it usually means LinuxCNC or the host PC has crashed.
or host communication to the FPGA card has been lost or serial communications
have been lost

 

Moderator could you please move this message to driver bords section. By mistake I asked the question in the wrong section, my appologies

From PCW response, if any peripheral card such as 7i77 watchdog HAS bit, the main power supply must be turned off.For implementation since 7i77 does not have a dedicated digital output. One way is to dedicate one preferable two of the 7i77 digital outputs to signal to the main power supply circuit to cut the power to the machine. I will update the schematic when I get chance.Good night, folks
 

a simplified example of hardwired estop/reset is posted in the hal examples section