Properties

Configuration, status and telemetry download from the device is handled using a number of property variables. Each variable has a type (signed/unsigned integers, floating point numbers, strings, etc.) and a default value. Some properties are used for configuration and can be modified and stored in (optionally write-protected) non-volatile memory. Others are read-only and used for telemetry purposes. Some property changes take effect immediately, while others require a store and a system reset after update.

The system properties are divided into a number of property groups, each covering a specific part of the firmware.

Property values can be listed, modified and stored using the prop debug shell commands or remotely through the Property Client Library. As an example, to change the CSP address of the device to 21 and the default interface to RS422/KISS, run:

[polaris] prop get sys.csp.address
20
[polaris] prop set sys.csp.address 21
[polaris] prop set sys.csp.routes "0/0 KISS"
[polaris] prop unlock sys
[polaris] prop save sys
[polaris] prop unlock -f sys
[polaris] prop save -f sys
[polaris] reboot
...
[polaris] prop get sys.csp.address
21
[polaris] prop get sys.csp.routes
"0/0 KISS"

System Group

The sys group contains system parameters which remain fixed after launch. The group can be stored twice in boot and fallback configuration. Both are write-protected and must be unlocked using prop unlock sys before they can be written to.

Property Type Default Description
sys.serial uint32 Serial number/ID of the device
sys.sw.version uint32 Running software version
sys.bootcount uint32 Number of times the system was booted
sys.csp.address uint8 20 CSP address of the device
sys.csp.routes string Additional CSP routes in CIDR notation
sys.can.rate uint32 1000000 CAN-bus bitrate
sys.rs422.rate uint32 1000000 RS422 baudrate

Configuration Group

The conf group contains runtime settings. The group can be stored to the boot configuration and is not write protected.

Property Type Default Description
conf.led.enable bool false Onboard LEDs enabled
conf.power.fpga bool false [1] FPGA power channel
conf.power.rf bool false [1] RF power channel
conf.power.sdcard bool false SD-card power channel
conf.power.eth bool false Ethernet power channel
conf.fs.mount bool false SD-card filesystem mount
conf.sdram.enable bool false Enable SDRAM
[1](1, 2) The power channels are powered off at boot time, but powered on when the demodulator starts.

Telemetry Group

Telemetry values are stored in the tm group and updated once every second. The group does not support storage.

Property Type Default Description
tm.temp.core int16 0 MCU junction temperature in 1/100 ℃
tm.temp.mcu int16 0 MCU package temperature in 1/100 ℃
tm.temp.fpga int16 0 FPGA junction temperature in 1/100 ℃
tm.temp.power int16 0 Power regulators temperature in 1/100 ℃
tm.temp.lna int16 0 LNA temperature in 1/100 ℃
tm.temp.adc int16 0 ADC temperature in 1/100 ℃
tm.temp.sdcard int16 0 SD-card temperature in 1/100 ℃
tm.volt.vin uint16 0 Input voltage in mV
tm.volt.3v3 uint16 0 3.3 V rail voltage in mV
tm.volt.2v0 uint16 0 2.0 V rail voltage in mV
tm.volt.1v0 uint16 0 1.0 V rail voltage in mV
tm.cur.vin int16 0 Input current in mA
tm.cur.3v3 int16 0 3.3 V rail current in mA
tm.cur.2v0 int16 0 2.0 V rail current in mA
tm.cur.1v0 int16 0 1.0 V rail current in mA
tm.power.vin uint16 0 Input power in mW
tm.power.3v3 uint16 0 3.3 V rail power in mW
tm.power.2v0 uint16 0 2.0 V rail power in mW
tm.power.1v0 uint16 0 1.0 V rail power in mW

Demodulator Group

The demod group contains configuration and information on the demodulator. The group can be stored to the boot configuration and is not write protected.

Property Type Default Description
demod.enable bool true Enable or disable demodulator
demod.decoded uint32 Number of decoded messages with correct FCS
demod.detected uint32 Number of detected messages
demod.rate uint16 Number of frames received in the last minute
demod.rf.gain float 0.0 Front end RF gain in dB
demod.pd.thres double 3.00 Packet detection threshold
demod.pd.winlen uint16 40 Packet detection window lenght
demod.pd.minlen uint16 1500 Packet detection minimum length
demod.scale.min uint16 Minimum scale parameter received
demod.scale.max uint16 Maximum scale parameter received
demod.mean.min int16 Minimum frequency offset received
demod.mean.max int16 Maximum frequency offset received

Store Group

The AIS message store is controlled and monitored through the store group. The group can be stored to the boot configuration and is not write protected.

Property Type Default Description
store.enable bool true Enable or disable message store
store.seq uint32 Last sequence number stored
store.stored uint32 Number of frames currently stored