7.2. Servicing Protocol (RS-232)

7.2. Servicing Protocol (RS-232)#

The servicing protocol is used to read and modify the operating parameters of the air quality meter. Device settings such as filtering parameters, measurement units selection, interface configuration, and other internal parameters are adjusted using this protocol.

Since the NMEA-like measurement protocol is unidirectional (measurement data is transmitted only from the device to the host), the servicing protocol provides independent two-way configuration and maintenance access on the same RS-232 interface when the device is awake. To simplify device setup and parameter adjustment, Geolux provides the Geolux Instrument Configurator software tool. End users typically do not need to interact directly with the servicing protocol, as all configuration tasks are performed through the Configurator application. A detailed description of the software is provided in Chapter 7 of this manual.

Each command must begin with the ‘#’ character and be terminated with a newline character. All standard combinations of carriage return (CR) and line feed (LF) characters (CR, LF, or CR+LF) are accepted as valid line termination.

Reading All Parameters at Once#

To read all parameters at once, send the following command to the device:

#get_info

The device will respond with a structured list of all current parameters and system information in the following format:

#modbus_address:0x01
#modbus_baudrate:115200
#modbus_parity:N
#modbus_stop_bits:1
#sdi12_address:0
#sdi12_sleep_mode:off
#serial_baudrate:115200
#serial_parity:N
#serial_stop_bits:1
#device_type:800
#serial_number:123455
#firmware_version:1.0.2
#hardware_version:RevA
#sensors_fw_ver:v1.4.35
#sensors_hw_ver:GEGSv2
#sensors_bl_ver:
#slot1_type:0
#slot2_type:1
#slot3_type:2
#slot4_type:3
#slot5_type:4
#sensors_status:1,1,1,1,1,1,1,1
#meas_valid:1,1,0,1,1,0,0,0
#blowout_faults:0,0
#blowout_period:0
#nmea:off
#modbus_transparent_mode:off
#sensors_modbus_address:0x06

The response includes device identification information (such as device type, firmware version, and serial number), followed by all configurable and status parameters. A complete description of all available parameters is provided later in this chapter.

Reading Single Parameter#

Any configuration parameter can be read individually:

#get_<parameter_name>

The device will respond:

#<parameter_name>: <value>

Writing Single Parameter#

Any configuration parameter that is not read-only can be changed by the following command format:

#set_parameter_name=value

The device will respond, depending on success or failure: :

#set_parameter_name:OK #set_parameter_name:ERR

List of Parameters#

  • #modbus_address: Modbus address of the device. This address is used when communicating with the device over the Modbus protocol.

  • #modbus_baudrate: Baud rate used for Modbus serial communication. It defines the communication speed in bits per second.

  • #modbus_parity: Parity setting used for Modbus serial communication. The value N indicates no parity.

  • #modbus_stop_bits: Number of stop bits used for Modbus serial communication.

  • #sdi12_address: SDI-12 address of the device used for communication on the SDI-12 bus.

  • #sdi12_sleep_mode: SDI-12 sleep mode setting. When enabled, the device may enter a low-power state between SDI-12 communication or measurement cycles.

  • #serial_baudrate: Baud rate used for standard serial communication. It defines the communication speed in bits per second.

  • #serial_parity: Parity setting used for standard serial communication. The value N indicates no parity.

  • #serial_stop_bits: Number of stop bits used for standard serial communication.

  • #device_type: Device type identifier. This value identifies the device model or product type.

  • #serial_number: Unique serial number of the device.

  • #firmware_version: Firmware version installed on the main device controller.

  • #hardware_version: Hardware revision of the main device electronics.

  • #sensors_fw_ver: Firmware version installed on the sensor module.

  • #sensors_hw_ver: Hardware revision of the sensor module.

  • #sensors_bl_ver: Bootloader version of the sensor module.

  • #slot1_type: Gas sensor type installed in gas sensor slot 1. Possible values are: 0 = CO, 1 = SO₂, 2 = NO, 3 = NO₂, 4 = O₃.

  • #slot2_type: Gas sensor type installed in gas sensor slot 2. Possible values are: 0 = CO, 1 = SO₂, 2 = NO, 3 = NO₂, 4 = O₃.

  • #slot3_type: Gas sensor type installed in gas sensor slot 3. Possible values are: 0 = CO, 1 = SO₂, 2 = NO, 3 = NO₂, 4 = O₃.

  • #slot4_type: Gas sensor type installed in gas sensor slot 4. Possible values are: 0 = CO, 1 = SO₂, 2 = NO, 3 = NO₂, 4 = O₃.

  • #slot5_type: Gas sensor type installed in gas sensor slot 5. Possible values are: 0 = CO, 1 = SO₂, 2 = NO, 3 = NO₂, 4 = O₃.

  • #sensors_status: Sensor activity status flags. Each value indicates whether the corresponding sensor or sensor group is active. 1 means that the sensor is active, while 0 means that the sensor is not active. The values are listed in the following order: gas slot 1, gas slot 2, gas slot 3, gas slot 4, gas slot 5, PM1, PM2.5, PM10.

  • #meas_valid: Measurement validity flags. Each value indicates whether the latest measurement from the corresponding sensor or sensor group is valid. 1 means that the measurement is valid, while 0 means that the measurement is not valid. The values are listed in the following order: gas slot 1, gas slot 2, gas slot 3, gas slot 4, gas slot 5, PM1, PM2.5, PM10.

  • #blowout_faults: Diagnostic flags related to the last performed blowout cycle. The first value indicates a pump fault and the second value indicates a valve fault. A value of 1 indicates a detected fault, while 0 indicates no fault. A fault is detected when the driver current exceeds 3.5 A, which typically indicates a short circuit in the pump or valve circuit.

  • #blowout_period: Configured blowout period in minutes. This parameter defines the interval or timing configuration for the automatic blowout function, depending on the device configuration.

  • #nmea: NMEA output setting. When enabled, the device outputs measurement data in NMEA-style message format.

  • #modbus_transparent_mode: Modbus transparent mode setting. When enabled, Modbus communication may be passed through to the internal sensor module.

  • #sensors_modbus_address: Modbus address of the internal sensor module. This address is used for communication with the sensor module over the internal or transparent Modbus interface.

Modbus Address#

Defines the Modbus address of the sensor. The accepted value range is from 1 to 247.

See Modbus ID for the detailed setting description.

Parameter name: modbus_address
Read command: #get_modbus_address
Write command: #set_mmodbus_address=<value>

Modbus Baud Rate#

Defines the baud rate of the RS485 port used for Modbus communication. The accepted values are:

See RS-485 Baud Rate for the detailed setting description.

1200 = 1200 bps,
2400 = 2400 bps,
4800 = 4800 bps,
9600 = 9600 bps,
14400 = 14400 bps,
19200 = 19200 bps,
38400 = 38400 bps,
57600 = 57600 bps, .
115200 = 115200 bps.
Parameter name: modbus_baud
Read command: #get_modbus_baud
Write command: #set_modbus_baud=<value>

Modbus Stop Bits#

Defines the number of stop bits used by the RS485 port for Modbus communication. The accepted values are:

See Stop Bits for the detailed setting description.

1 = one stop bit,
2 = two stop bits.
Parameter name: modbus_stop_bits
Read command: #get_modbus_stop_bits
Write command: #set_modbus_stop_bits=<value>

Modbus Serial Line Parity#

Gets / sets the serial line parity for RS-485 / Modbus connection. The change takes place immediately. The accepted values are:

See Parity for the detailed setting description.

none,
odd,
even.
Parameter name: modbus_parity
Read command: #get_modbus_parity
Write command: #set_modbus_parity=<value>

SDI-12 Address#

Address of the device on the SDI-12 bus. Valid range is 0-61, which will be converted to characters 0-9, A-Z and a-z.

See SDI-12 ID for the detailed setting description.

Parameter name: sdi_id
Read command: #get_sdi_id
Write command: #set_sdi_id=<value>

Serial Baud Rate#

Defines the baud rate of the RS485 port used for Serial communication. The accepted values are:

See RS-232 Baud Rate for the detailed setting description.

1200 = 1200 bps,
2400 = 2400 bps,
4800 = 4800 bps,
9600 = 9600 bps,
14400 = 14400 bps,
19200 = 19200 bps,
38400 = 38400 bps,
57600 = 57600 bps, .
115200 = 115200 bps.
Parameter name: serial_baud
Read command: #get_serial_baud
Write command: #set_serial_baud=<value>

Serial Stop Bits#

Defines the number of stop bits used by the RS232 port for Serial communication. The accepted values are:

See RS232 Stop Bits for the detailed setting description.

1 = one stop bit,
2 = two stop bits.
Parameter name: serial_stop_bits
Read command: #get_serial_stop_bits
Write command: #set_serial_stop_bits=<value>

Serial Line Parity#

Gets / sets the serial line parity for RS-232 / Serial connection. The change takes place immediately. The accepted values are:

See Serial Parity for the detailed setting description.

none,
odd,
even.
Parameter name: serial_parity
Read command: #get_serial_parity
Write command: #set_serial_parity=<value>

Blowout#

Starts one chamber blowout.

See Blowout period for the detailed setting description.

Parameter name: blowout
Write command: #blowout

Blowout Period#

Defines the blowout period in minutes. If d = 0, blowout is manual. Starts one chamber blowout and then starts the period d.

See Blowout period for the detailed setting description.

Parameter name: blowout_period
Write command: #set_blowout_period=<d>

Enable NMEA#

Enables NMEA to run in the background.

Parameter name: enable_nmea
Write command: #enable_nmea

Disable NMEA#

Disables NMEA. NMEA is automatically enabled again on the next sensor power-up.

Parameter name: disable_nmea
Write command: #disable_nmea

Factory Reset#

Resets all settings to default values. Hardware revision and serial number are not erased.

Parameter name: factory_reset
Write command: #factory_reset

Enable SDI-12 Sleep#

Enables SDI-12 sleep mode. The sensor sleeps and wakes up on each SDI-12 command. After the measurement is completed, the sensor returns to sleep mode.

Parameter name: enable_sdi12_sleep
Write command: #enable_sdi12_sleep

Disable SDI-12 Sleep#

Disables SDI-12 sleep mode and puts the sensor into continuous / normal operating mode.

Parameter name: disable_sdi12_sleep
Write command: #disable_sdi12_sleep

Reset#

Resets the complete AX500.

Parameter name: reset
Write command: #reset

Reset Sensors#

Resets only the Sensor module.

Parameter name: reset_sensors
Write command: #reset_sensors