Control Block Description ADDvantage-32
4-29
4.20 COM WD
FIGURE 4-20. COM WD BLOCK
1. Inputs
EN: Bit
WD IP: Bit
TOUT: Analog
2.
Outputs
WDOUT Bit
TRIP Bit
3.
Implementation
When the EN input of the WD COM block is a logic level high (One Bit), the block
monitors the WDIN input and will set the TRIP output if the input fails to toggle
(transition from low to high or transition from high to low) within the time period
(seconds) defined by the TOUT input. The WD OUT bit equates to the bit inverted state
of the WDIN input. The TRIP output will be reset to a logic level low (Zero Bit) when
the EN input is set to a logic level low signal or if the WDIN begins to toggle at a rate
greater than the TOUT time period.