def Init_IOPi():
global sensorbus
global buttonbus
i2c_helper = ABEHelpers()
i2c_bus = i2c_helper.get_smbus()
sensorbus = IoPi(i2c_bus, 0x20)
# set both rows of pins to input mode
sensorbus.set_port_direction(0, 0xFF)
sensorbus.set_port_direction(1, 0xFF)
#setup interrupts on bus 2, port 1
buttonbus = IoPi(i2c_bus, 0x21)
# Set all pins on the bus to be inputs with internal pull-ups enabled.
buttonbus.set_port_pullups(1, 0xFF)
buttonbus.set_port_direction(1, 0xFF)
# Inverting the ports will allow a button connected to ground to register as 1 or on.
buttonbus.invert_port(1, 0xFF) # invert port 1 so a button press will register as 1
# Set the interrupt polarity to be active low and mirroring enabled, so
# INT A and INT B go low when an interrupt is triggered
buttonbus.set_interrupt_polarity(0)
#buttonbus.mirror_interrupts(1)
# Set the interrupts default value to 0 so it will trigger when any of the pins on the bus change to 1
buttonbus.set_interrupt_defaults(1, 0x00)
# Set the interrupt type to be 0xFF for port B so an interrupt is
# fired when the pin matches the default value
buttonbus.set_interrupt_type(1, 0xFF)
# Enable interrupts for all pins on the port
buttonbus.set_interrupt_on_port(1, 0xFF)
# reset the interrups on the IO Pi bus
buttonbus.reset_interrupts()
GPIO.setmode(GPIO.BCM)
# Set up GPIO 23 as an input. The pull-up resistor is disabled as the level shifter will act as a pull-up.
GPIO.setup(23, GPIO.IN, pull_up_down=GPIO.PUD_OFF)
# when a falling edge is detected on GPIO pin 23 the function button_pressed will be run
GPIO.add_event_detect(23, GPIO.FALLING, callback=hwbutton_pressed)
# Set all pins on bus 2 to be inputs with internal pull-ups disabled.
bus2.set_port_pullups(0, 0x00)
bus2.set_port_pullups(1, 0x00)
bus2.set_port_direction(0, 0xFF)
bus2.set_port_direction(1, 0xFF)
# Set the interrupt polarity to be active high and mirroring disabled, so
# pins 1 to 8 trigger INT A and pins 9 to 16 trigger INT B
bus2.set_interrupt_polarity(1)
bus2.mirror_interrupts(0)
# Set the interrupts default value to trigger when 5V is applied to pins 1
# and 16
bus2.set_interrupt_defaults(0, 0x01)
bus2.set_interrupt_defaults(0, 0x80)
# Set the interrupt type to be 1 for ports A and B so an interrupt is
# fired when the pin matches the default value
bus2.set_interrupt_type(0, 1)
bus2.set_interrupt_type(1, 1)
# Enable interrupts for pins 1 and 16
bus2.set_interrupt_on_pin(1, 1)
bus2.set_interrupt_on_pin(16, 1)
while True:
# read the port value from the last capture for ports 0 and 1. This will
# reset the interrupts
bus.set_port_direction(1, 0xFF) # Inverting the ports will allow a button connected to ground to register as 1 or on. bus.invert_port(0, 0xFF) # invert port 0 so a button press will register as 1 bus.invert_port(1, 0xFF) # invert port 1 so a button press will register as 1 # Set the interrupt polarity to be active low and mirroring enabled, so # INT A and INT B go low when an interrupt is triggered bus.set_interrupt_polarity(0) bus.mirror_interrupts(1) # Set the interrupts default value to 0 so it will trigger when any of the pins on the bus change to 1 bus.set_interrupt_defaults(0, 0x00) bus.set_interrupt_defaults(1, 0x00) # Set the interrupt type to be 0xFF for ports A and B so an interrupt is # fired when the pin matches the default value bus.set_interrupt_type(0, 0xFF) bus.set_interrupt_type(1, 0xFF) # Enable interrupts for all pins on the bus bus.set_interrupt_on_port(0, 0xFF) bus.set_interrupt_on_port(1, 0xFF) # reset the interrups on the IO Pi bus
# Set all pins on bus 2 to be inputs with internal pull-ups disabled.
bus2.set_port_pullups(0, 0x00)
bus2.set_port_pullups(1, 0x00)
bus2.set_port_direction(0, 0xFF)
bus2.set_port_direction(1, 0xFF)
# Set the interrupt polarity to be active high and mirroring disabled, so
# pins 1 to 8 trigger INT A and pins 9 to 16 trigger INT B
bus2.set_interrupt_polarity(1)
bus2.mirror_interrupts(0)
# Set the interrupts default value to trigger when 5V is applied to pins 1
# and 16
bus2.set_interrupt_defaults(0, 0x01)
bus2.set_interrupt_defaults(0, 0x80)
# Set the interrupt type to be 1 for ports A and B so an interrupt is
# fired when the pin matches the default value
bus2.set_interrupt_type(0, 1)
bus2.set_interrupt_type(1, 1)
# Enable interrupts for pins 1 and 16
bus2.set_interrupt_on_pin(1, 1)
bus2.set_interrupt_on_pin(16, 1)
while True:
# read the port value from the last capture for ports 0 and 1. This will
