def set_fan_rpm_gs3(ser, slave_address, rpm_setting, max_rpm):
"""
Set the fan speed in rpm on a gs3 fan controller.
:param ser: Serial connection to the gs3 fan controller.
Contains baud rate, parity, and timeout.
:param slave_address: The Modbus slave address of the device.
:param rpm_setting: The user supplied rpm setting.
:param max_rpm: The max rpm setting for the fan motor.
:return: The modbus write result.
"""
client = dkmodbus.dkmodbus(ser)
if rpm_setting == 0: # Turn the fan off.
result = client.write_multiple_registers(
slave_address, # Slave address.
0x91B, # Register to write to.
1, # Number of registers to write to.
2, # Number of bytes to write.
'\x00\x00') # Data to write.
else: # Turn the fan on at the desired RPM.
rpm_to_hz = get_fan_rpm_to_hz_gs3(client.serial_device, slave_address,
max_rpm)
hz = rpm_setting * rpm_to_hz
packed_hz = conversions.fan_gs3_packed_hz(hz)
result = client.write_multiple_registers(
1, # Slave address.
0x91A, # Register to write to.
2, # Number of registers to write to.
4, # Number of bytes to write.
packed_hz + '\x00\x01'
) # Frequency setting in Hz / data # 01 is on, # 00 is off.
return result
def read_holding_register(ser, slave_address, register):
"""Read a holding register from an RS485 device.
:param ser: Serial connection to the gs3 fan controller.
Contains baud rate, parity, and timeout.
:param slave_address: The Modbus slave address of the device.
:param register: The register to read (int).
:returns The register reading (int).
"""
client = dkmodbus.dkmodbus(ser)
register_data = client.read_holding_registers(slave_address, register, 1)
result = conversions.unpack_word(register_data)
print '0x{}'.format(result)
return result
def read_holding_register(ser, slave_address, register):
"""Read a holding register from an RS485 device.
:param ser: Serial connection to the fan controller.
Contains baud rate, parity, and timeout.
:param slave_address: The Modbus slave address of the device.
:param register: The register to read (int).
:returns The register reading (int).
"""
client = dkmodbus.dkmodbus(ser)
register_data = client.read_holding_registers(slave_address, register, 1)
result = unpack_register_data(register_data)
logger.debug('read_holding_register result: {}, type: {}'.format(
result, type(result)))
return result
def create_modbus_client(self):
"""Production hardware only wrapper for creating the serial device that
we use to speak modbus to the CEC (Central Exhaust Chamber) board.
This will not work for the emulator.
:returns: The dkmodbus client."""
# Test that the usb device is there. If not, reset the usb.
if not os.path.exists(self.device_name):
dkmodbus.dkmodbus.reset_usb([1, 2])
ser = serial.Serial(
self.device_name, # Serial device name.
baudrate=self.baud_rate,
parity=self.parity,
timeout=self.timeout)
return dkmodbus.dkmodbus(ser)
def set_fan_rpm_ecblue(ser, slave_address, rpm_setting, max_rpm):
"""
Set the fan speed in rpm on an ECblue fan controller.
:param ser: Serial connection to the gs3 fan controller.
Contains baud rate, parity, and timeout.
:param slave_address: The Modbus slave address of the device.
:param rpm_setting: The user supplied rpm setting.
:param max_rpm: The max rpm setting for the fan motor.
:return: The modbus write result.
"""
client = dkmodbus.dkmodbus(ser)
logger.debug('Setting fan speed. max_rpm: {}, rpm_setting: {}'.format(
max_rpm, rpm_setting))
percentage_setting = float(rpm_setting) / float(max_rpm)
logger.debug('percentage_setting: {}'.format(percentage_setting))
fan_setting_decimal = int(percentage_setting * float(600.0))
logger.debug('fan_setting_decimal: {}d 0x{:04x}'.format(
fan_setting_decimal, fan_setting_decimal))
fan_setting = (fan_setting_decimal / 100) << 8
logger.debug('fan_setting: {}d 0x{}'.format(fan_setting, fan_setting))
setting = ((fan_setting_decimal % 100) / 10) << 4
fan_setting += setting
logger.debug('fan_setting: {}d 0x{}'.format(fan_setting, fan_setting))
setting = (fan_setting_decimal % 10)
fan_setting += setting
logger.debug('fan_setting: {}d 0x{}'.format(fan_setting, fan_setting))
fan_setting = struct.pack('>H', fan_setting)
result = client.write_multiple_registers(
slave_address, # Slave address.
2, # Register to write to.
1, # Number of registers to write to.
2, # Number of bytes to write.
fan_setting) # Data to write.
return result