main.py

# PSM API is quite simple and just has a few functions. When writing your
# own programs, avoid touching on the "__main__" function as this regulates
# how PSM works on the PLC cycle. You can write your own hardware initialization
# code on hardware_init(), and your IO handling code on update_inputs() and
# update_outputs()
#
# To manipulate IOs, just use PSM calls psm.get_var([location name]) to read
# an OpenPLC location and psm.set_var([location name], [value]) to write to
# an OpenPLC location. For example:
#     psm.get_var("QX0.0")
# will read the value of %QX0.0. Also:
#     psm.set_var("IX0.0", True)
# will set %IX0.0 to true.
#
# Below you will find a simple example that uses PSM to switch OpenPLC's
# first digital input (%IX0.0) every second. Also, if the first digital
# output (%QX0.0) is true, PSM will display "QX0.0 is true" on OpenPLC's
# dashboard. Feel free to reuse this skeleton to write whatever you want.

from psm import psm
import time
import yaml


with open('config.yaml', 'r') as file:
    config = yaml.safe_load(file)

counter = 0
var_state = False

def hardware_init():
    #Insert your hardware initialization code in here
    server_settings = (config['server']['host'], config['server']['port'])  # (hostname, port)
    psm.start(server_settings)

def update_inputs():
    #place here your code to update inputs
    global counter
    global var_state
    psm.set_var("IX0.0", var_state)
    counter += 1
    if (counter == 10):
        counter = 0
        var_state = not var_state
    
def update_outputs():
    #place here your code to work on outputs
    a = psm.get_var("QX0.0")
    if a == True:
        print("QX0.0 is true")

if __name__ == "__main__":
    hardware_init()
    while (not psm.should_quit()):
        update_inputs()
        update_outputs()
        time.sleep(0.1) #You can adjust the psm cycle time here
    psm.stop()