This example brings together LEDs, button input, and a servo all operating at the same time without interfering with one another.
When you press the button it will switch to blinking the opposite pair of LEDs by swapping the dictionaries into and out of the BLINK_LIST using the pop() and append() functions.
"""
This example script shows the usage of servos, LEDs, and buttons all
used simultaneously without interrupting each other.
"""
import time
import board
import digitalio
import neopixel
import pwmio
from adafruit_motor import servo
from digitalio import DigitalInOut, Direction, Pull
btn = DigitalInOut(board.SWITCH)
btn.direction = Direction.INPUT
btn.pull = Pull.UP
prev_state = btn.value
pixels = neopixel.NeoPixel(board.NEOPIXEL, 1)
pixels[0] = (0, 0, 0)
BLINK_LIST = [
{
"ON": 0.5,
"OFF": 0.5,
"PREV_TIME": -1,
"PIN": board.D5,
},
{
"ON": 0.5,
"OFF": 0.5,
"PREV_TIME": -1,
"PIN": board.D6,
},
{
"ON": 0.5,
"OFF": 0.5,
"PREV_TIME": -1,
"PIN": board.D9,
},
{
"ON": 0.5,
"OFF": 0.5,
"PREV_TIME": -1,
"PIN": board.D10,
}
]
SERVO_LIST = [
{
"MAX_ANGLE": 180,
"MIN_ANGLE": 0,
"PREV_TIME": -1,
"PIN": board.A1,
"DELAY_BETWEEN": 0.05,
"SERVO": None,
"MOVE_BY": 5
},
{
"MAX_ANGLE": 90,
"MIN_ANGLE": 0,
"PREV_TIME": -1,
"PIN": board.A3,
"DELAY_BETWEEN": 0.02,
"SERVO": None,
"MOVE_BY": 2
}
]
for cur_servo in SERVO_LIST:
pwm = pwmio.PWMOut(cur_servo["PIN"], duty_cycle=2 ** 15, frequency=50)
# Create a servo object.
cur_servo["SERVO"] = servo.Servo(pwm)
for led in BLINK_LIST:
led["PIN"] = digitalio.DigitalInOut(led["PIN"])
led["PIN"].direction = digitalio.Direction.OUTPUT
disabled_leds = []
# temporarily remove first two from the blink list
disabled_leds.append(BLINK_LIST.pop(0))
disabled_leds.append(BLINK_LIST.pop(0))
while True:
# Store the current time to refer to later.
now = time.monotonic()
cur_state = btn.value
if cur_state != prev_state:
if not cur_state:
print("BTN is down")
# swap the LED Blink patterns to the opposite pairs of LEDs
temp = []
temp.append(BLINK_LIST.pop(0))
temp.append(BLINK_LIST.pop(0))
BLINK_LIST.append(disabled_leds.pop(0))
BLINK_LIST.append(disabled_leds.pop(0))
disabled_leds.append(temp.pop(0))
disabled_leds.append(temp.pop(0))
else:
print("BTN is up")
prev_state = cur_state
for led in BLINK_LIST:
if led["PIN"].value is False:
if now >= led["PREV_TIME"] + led["OFF"]:
led["PREV_TIME"] = now
led["PIN"].value = True
if led["PIN"].value is True:
if now >= led["PREV_TIME"] + led["ON"]:
led["PREV_TIME"] = now
led["PIN"].value = False
for servo in SERVO_LIST:
if now >= servo["PREV_TIME"] + servo["DELAY_BETWEEN"]:
try:
servo["SERVO"].angle += servo["MOVE_BY"]
except ValueError as e:
if servo["MOVE_BY"] > 0:
servo["SERVO"].angle = servo["MAX_ANGLE"]
else:
servo["SERVO"].angle = servo["MIN_ANGLE"]
if servo["SERVO"].angle >= servo["MAX_ANGLE"] or \
servo["SERVO"].angle <= servo["MIN_ANGLE"]:
servo["MOVE_BY"] = -servo["MOVE_BY"]
servo["PREV_TIME"] = now
