def analog_sensor_power(cls, bus, operation):
""" Method that turns on all of the analog sensor modules
Includes all attached soil moisture sensors
Note that all of the SensorCluster object should be attached
in parallel and only 1 GPIO pin is available
to toggle analog sensor power.
The sensor power should be left on for at least 100ms
in order to allow the sensors to stabilize before reading.
Usage: SensorCluster.analog_sensor_power(bus,"high")
OR SensorCluster.analog_sensor_power(bus,"low")
This method should be removed if an off-board GPIO extender is used.
"""
# Set appropriate analog sensor power bit in GPIO mask
# using the ControlCluster bank_mask to avoid overwriting any data
reg_data = get_IO_reg(bus, 0x20, cls.power_bank)
if operation == "on":
reg_data = reg_data | 1 << cls.analog_power_pin
elif operation == "off":
reg_data = reg_data & (0b11111111 ^ (1 << cls.analog_power_pin))
else:
raise SensorError(
"Invalid command used while enabling analog sensors")
# Send updated IO mask to output
IO_expander_output(bus, 0x20, cls.power_bank, reg_data)
def restore_state(self):
""" Method should be called on obj. initialization
When called, the method will attempt to restore
IO expander and RPi coherence and restore
local knowledge across a possible power failure
"""
current_mask = get_IO_reg(ControlCluster.bus,
self.IOexpander,
self.bank)
if current_mask & (1 << ControlCluster.pump_pin):
self.manage_pump("on")
if current_mask & (1 << self.fan):
self.manage_fan("on")
if current_mask & (1 << self.light):
self.manage_fan("on")
