Photo-gate timer with CircuitPython

CircuitPython

CircuitPython is a flavor or port of MicroPython, by Adafruit Industries, to program any of hundreds of micro-controllers or single-board-computers with Python code. Changing the code on a board is simple: You copy a Python program file, and optionally libraries, to board that can be set to present itself to a computer as a USB drive. When you reset the board, it runs the file.

ESP32-S2 Reverse TFT Feather

The ESP32-S2 Reverse TFT Feather from Adafruit, https://www.adafruit.com/product/5345 , is an inexpensive development board with a WiFi capable

Code

import time import board import keypad print("Photogate timer") gates = (board.D1, board.D2) #create empty list: times = [] #track which gates have already been interrupted passed = [] #interval is time in seconds to debounce button. keys = keypad.Keys(gates, value_when_pressed=True, pull=True, interval=0.002) while True: event=keys.events.get() if event: #print(event) #uncomment this to debug events #which gate was passed? event.key_number #if this is the first gate: if 0 == len(times): times.append(0.0) startTime = time.monotonic() #mark which gate has been passed passed.append(event.key_number) print(times) #else check if a gate not yet passed: elif 0 == passed.count(event.key_number): #Add the current time to the list times.append(time.monotonic() - startTime) passed.append(event.key_number) print(times)