Technical information

OPTO DIO Reference Read This First.
the external isolated power supply applied.
Do not make any assumptions about the effects of changes
made to the external circuit if the power off and reset conditions
are critical to the safe operation of your system.
Figure 1-12. Input Port Schematic.______________________________
Input Port Schematic.___________________
The input port schematic is given in Figure 1-12. The input
port lines are reverse connection protected and current limited.
Input voltages of 0.0 - 2.38 Volts read as input logic low, 0.
Input voltages of 2.4 - 24.00 Volts read as input logic high, 1.
The inputs are current limited by a 3k3 Ohm resistor and
are reverse connection protected by diodes.
The Watch Dog.______________
The watch dog is a failsafe method of ensuring that the
user’s program is still running correctly. On power up, the watch
dog is disabled. If the user’s program enables the watchdog, an
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