GuyCarver-MicroPython/lib/bts7960.py

65 wiersze
1.7 KiB
Python

#Driver for the bts7960 43A high power motor controller.
from pwm import pwm
from pyb import Pin
from utime import sleep_ms
class motor( ):
"""Control a motor connected to the bts7960 motor controller."""
def __init__( self, aOnOff, aForward, aBackward ) :
"""aOnOff is the pin to control free movement of the motor.
aForward and aBackward are tuples indicating pin and timer channel # for PWM pins.
aForward = (pin name, timer channel #)
aBackward = (pin name, timer channel #)
Need to make sure the given timer channel # is associated with the pin
or an exception will be raised.
#Examples:
m1 = motor('Y1', ('Y2', 8), ('Y3', 10))
m2 = motor('X1', ('X2', 5), ('X3', 5)) """
self._onoff = Pin(aOnOff, Pin.OUT_PP)
self._forward = pwm(*aForward)
self._backward = pwm(*aBackward)
self._speed = 0
self.seton( self, aOn ) :
'''Set on/off (free wheeling) state of motor.'''
if aOn :
self._onoff.high()
else:
self._onoff.low()
@property
def speed( self ) : return self._speed
@speed.setter
def speed( self, aValue ) :
'''Set velocity and direction of motor with -100 <= aValue <= 100.'''
self._speed = aValue
on = False
f = 0
b = 0
if aValue < 0 :
on = True
f = 0
b = min(100, -aValue)
else:
on = True
f = min(100, aValue)
b = 0
self.seton(on)
self._forward.pulse_width_percent = f
self._backward.pulse_width_percent = b
def brake( self ) :
""" Brake the motor by sending power both directions, then shut it all down. """
self._forward.pulse_width_percent = 100
self._backward.pulse_width_percent = 100
self.seton(True)
sleep_ms(500)
self.speed = 0