Logic gates on the TinySpark development board

Now that the first neuron 'network' was succesfully implemented, it will be transported to the TinySpark development kit.

The two buttons, Button 1 and Button 2 on the development kit will be used to simulate the inputs, and thee LED (LED13) will be used to show if the output of the neuron 'network' is LOW/0 or HIGH/1. In order to access the Inputs and Outputs of the development kit, some code is needed. The code below combines the example code for interaction with the buttons and output through the LED.

input_output.py

# import the library to take care of the pins
import board
from digitalio import DigitalInOut, Direction, Pull

# initialise the pins
button1 = DigitalInOut(board.BUTTON1)
button1.direction = Direction.INPUT
button1.pull = Pull.UP
button2 = DigitalInOut(board.BUTTON2)
button2.direction = Direction.INPUT
button2.pull = Pull.UP
led = DigitalInOut(board.LED)
led.direction = Direction.OUTPUT

# turn the LED on
led.value = True

# loop endlessly
while 1:
    # check if a button is pressed, and print if it is (buttons are pulled HIGH, so check for low)
    if not button1.value:
        print("button1 pressed")
    if not button2.value:
        print("button2 pressed")

Now the logic from the previous section needs to be implemented, in order to complete the neuron 'network' and succesfully deploy it to the TinySpark development board.

OR_gate.py

# import the library to take care of the pins
import board
from digitalio import DigitalInOut, Direction, Pull

# initialise the pins
button1 = DigitalInOut(board.BUTTON1)
button1.direction = Direction.INPUT
button1.pull = Pull.UP
button2 = DigitalInOut(board.BUTTON2)
button2.direction = Direction.INPUT
button2.pull = Pull.UP
led = DigitalInOut(board.LED)
led.direction = Direction.OUTPUT

# store the weights
weight1 = 0.5
weight2 = 0.9

# loop endlessly
while 1:
    # Read the button value (buttons are pulled HIGH, so check for low)
    input1 = button1.value
    input2 = button2.value

    sum = (input1 * weight1) + (input2 * weight2)
    if sum >= 0.5:
        # activation = 1
        led.value = True
    else:
        # activation = 0
        led.value = False

Upload the code and see if the neuron 'network' functions as expected, by pressing Button 1 and Button 2 and observing the LED.

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In the next chapter, some more complicated predictions will be made by utilising an actual network of neurons.