Definition
wait_digital_input(index, val, timeout=None)
Features
This function waits until the signal value of the digital input register of the controller becomes val (ON or OFF). The waiting time can be changed with a timeout setting. The waiting time ends, and the result is returned if the waiting time has passed. This function waits indefinitely if the timeout is not set.
Parameters
|
Parameter Name |
Data Type |
Default Value |
Description |
|---|---|---|---|
|
index |
int |
- |
A number 1 - 20 which means the I/O index mounted on the controller.
|
|
val |
int |
- |
I/O value
|
|
timeout |
float |
- |
Waiting time (sec) This function waits indefinitely if the timeout is not set. |
Return
|
Value |
Description |
|---|---|
|
0 |
Success |
|
-1 |
Failed (time-out) |
Exception
|
Exception |
Description |
|---|---|
|
DR_Error (DR_ERROR_TYPE) |
Parameter data type error occurred |
|
DR_Error (DR_ERROR_VALUE) |
Parameter value is invalid |
|
DR_Error (DR_ERROR_RUNTIME) |
C extension module error occurred |
|
DR_Error (DR_ERROR_STOP) |
Program terminated forcefully |
Example
wait_digital_input(1, ON) # Indefinite wait until the no. 1 contact becomes ON
wait_digital_input(2, OFF) # Indefinite wait until the no. 2 contact becomes OFF
res = wait_digital_input(1, ON, 3) # Wait for up to 3 seconds until the no. 1 contact becomes ON
# Waiting is terminated and res = 0 if the no. 1 contact becomes ON within 3 seconds.
# Waiting is terminated and res = -1 if the no. 1 contact does not become ON within 3 seconds.