def initPCA9685(self):
"""
@description configure Jetson Nano GPIO for communication with PCA9685
@return a PCA9685 Device object to communicate with PCA9685 chip
"""
GPIO.setmode(GPIO.BOARD)
mode = GPIO.getmode()
print("Jetson Nano GPIO Mode: {}".format(mode))
# discover I2C devices
i2c_devs = Device.get_i2c_bus_numbers()
print("The following /dev/i2c-* devices were found:\n{}".format(
i2c_devs))
# Create I2C device
"""
working_devs = list()
print("Looking out which /dev/i2c-* devices is connected to PCA9685")
for dev in i2c_devs:
try:
pca9685 = Device(0x40,dev)
# Set duty cycle
pca9685.set_pwm(5, 2047)
# set pwm freq
pca9685.set_pwm_frequency(1000)
print("Device {} works!".format(dev))
working_devs.append(dev)
except:
print("Device {} does not work.".format(dev))
# Select any working device, for example, the first one
print("Configuring PCA9685 connected to /dev/i2c-{} device.".format(working_devs[0]))
pca9685 = Device(0x40, working_devs[0])
"""
pca9685 = Device(
0x40, 1
) # Immediately set a working device, this assumes PCA9685 is connected to I2C channel 1
# ESC work at 50Hz
pca9685.set_pwm_frequency(50)
# Set slow speed duty cycles
self.set_channel_duty_cycle(pca9685, 0, 5.0)
self.set_channel_duty_cycle(pca9685, 1, 5.0)
self.set_channel_duty_cycle(pca9685, 2, 5.0)
self.set_channel_duty_cycle(pca9685, 3, 5.0)
# configure rest of channels to 0 duty cycle
rest = np.arange(4, 16, 1)
for channel in rest:
self.set_channel_duty_cycle(pca9685, channel, 0.0)
return pca9685
"""
@pwmdev a Device class object already configured
@channel Channel or PIN number in PCA9685 to configure 0-15
@dt desired duty cycle
"""
val = (dt * 4095) // 100
pwmdev.set_pwm(channel, val)
# SET GPIO mode to BOARD
GPIO.setmode(GPIO.BOARD)
mode = GPIO.getmode()
print(mode)
# discover I2C devices
i2c_devs = Device.get_i2c_bus_numbers()
print("The following /dev/i2c-* devices were found:\n{}".format(i2c_devs))
# Create I2C device
working_devs = list()
print("Looking out which /dev/i2c-* devices is connected to PCA9685")
for dev in i2c_devs:
try:
pca9685 = Device(0x40, dev)
# Set duty cycle
pca9685.set_pwm(5, 2047)
# set pwm freq
pca9685.set_pwm_frequency(1000)
print("Device {} works!".format(dev))
working_devs.append(dev)
