import time
from servo import Servos
from machine import SoftI2C, Pin
i2c = SoftI2C(sda=Pin('P5'), scl=Pin('P4'))
servo = Servos(i2c, address=0x40, freq=50, min_us=500, max_us=2500, degrees=180)
while True:
servo.position(8, 180)
import utime
import ustruct
class PCA9685:
def __init__(self, i2c, address=0x40):
self.i2c = i2c
self.address = address
self.reset()
def _write(self, address, value):
self.i2c.writeto_mem(self.address, address, bytearray([value]))
def _read(self, address):
return self.i2c.readfrom_mem(self.address, address, 1)[0]
def reset(self):
self._write(0x00, 0x00) # Mode1
def freq(self, freq=None):
if freq is None:
return int(25000000.0 / 4096 / (self._read(0xfe) - 0.5))
prescale = int(25000000.0 / 4096.0 / freq + 0.5)
old_mode = self._read(0x00) # Mode 1
self._write(0x00, (old_mode & 0x7F) | 0x10) # Mode 1, sleep
self._write(0xfe, prescale) # Prescale
self._write(0x00, old_mode) # Mode 1
utime.sleep_us(5)
self._write(0x00, old_mode | 0xa1) # Mode 1, autoincrement on
def pwm(self, index, on=None, off=None):
if on is None or off is None:
data = self.i2c.readfrom_mem(self.address, 0x06 + 4 * index, 4)
return ustruct.unpack('<HH', data)
data = ustruct.pack('<HH', on, off)
self.i2c.writeto_mem(self.address, 0x06 + 4 * index, data)
def duty(self, index, value=None, invert=False):
if value is None:
pwm = self.pwm(index)
if pwm == (0, 4096):
value = 0
elif pwm == (4096, 0):
value = 4095
value = pwm[1]
if invert:
value = 4095 - value
return value
if not 0 <= value <= 4095:
raise ValueError("Out of range")
if invert:
value = 4095 - value
if value == 0:
self.pwm(index, 0, 4096)
elif value == 4095:
self.pwm(index, 4096, 0)
else:
self.pwm(index, 0, value)
import pca9685
import math
class Servos:
def __init__(self, i2c, address=0x40, freq=50, min_us=600, max_us=2400, degrees=180):
self.period = 1000000 / freq
self.min_duty = self._us2duty(min_us)
self.max_duty = self._us2duty(max_us)
self.degrees = degrees
self.freq = freq
self.pca9685 = pca9685.PCA9685(i2c, address)
self.pca9685.freq(freq)
def _us2duty(self, value):
return int(4095 * value / self.period)
def position(self, index, degrees=None, radians=None, us=None, duty=None):
span = self.max_duty - self.min_duty
if degrees is not None:
duty = self.min_duty + span * degrees / self.degrees
elif radians is not None:
duty = self.min_duty + span * radians / math.radians(self.degrees)
elif us is not None:
duty = self._us2duty(us)
elif duty is not None:
pass
else:
return self.pca9685.duty(index)
duty = min(self.max_duty, max(self.min_duty, int(duty)))
self.pca9685.duty(index, duty)
def release(self, index):
self.pca9685.duty(index, 0)