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Relay Preserve State Sample

This sample demonstrates state preserve functionality of the Relay HAT.

To run the sample:

  1. 2.
    Copy the sample code to a folder on the Raspberry Pi.
  2. 3.
    Open terminal, and then go to the folder you copied the sample.
  3. 4.
    Run the sample with the following command:
python3 Relay_Preserve_State.py

Sample Code

Relay_Preserve_State.py
#!/usr/bin/env python3
#This sample demonstrates state preserve functionality of the Relay HAT.
#Install Relay HAT 2 library with "pip3 install turta-relayhat2"
from time import sleep
from turta_relayhat2 import Turta_Relay
#Initialize
relay = Turta_Relay.RelayController(preserve_state = True)
#Read and increment the current relay state
state = relay.read_all() + 1
if (state == 32):
state = 0
#Set the new relay state
relay.write_once(state)
print("Relay state is set")

Result

When you run the sample, the relay states are changed every two seconds. The example output should be like this:
Relay state is set
To stop the Python script, just press CTRL + C.