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 # TrainCircuit
 
-Codes for my father train circuit
\ No newline at end of file
+Codes for my father train circuit
+
+
+## Relays control
+The relays boards must first have the following connections:
+* GND (relays board) => GND (raspberry PI card)
+* VCC (relays board) => 5V (raspberry PI card)
+* Each INx on the relays board must be mapped to a GPIO pin of the Raspberry Pi
+
+Use `GPIO.output(num, True)` to stop a relay and `GPIO.output(num, False)` to start it again.
+