The external control of the satellite is possible through the serial UART link. Since the hard-connected cable interface is not possible in space, the full control is implemented through the communication board. The LitSat-1 satellite is controlled by commands transmitted using the AX.25 protocol. The data baudrate is 9600 bps.
The list of possible commands:
- satellite nodes control
- connecting and disconnecting of the power supply for most of the nodes
- connecting and disconnecting of the linear transponder
- controlling the power of GPS- GLONAS navigation transceiver
- turning on and turning off the silent mode of GPS- GLONAS navigation receiver
- restarting the satellite
- other
- request for information
- additional data of all sensors
- voltage, current, power from solar batteries
- voltage, current, power used by different modules
- total amounts of voltage, current, power
- telemetric measurement data, 10 Hz frequency (after the release of the satellite)
The satellite will broadcast the telemetric package AX.25 every 4567 milliseconds. The package will contain the main information about the satellite: lifetime, data of the sensors, energy parameters, GPS coordinates and speed (only after a GPS receiver is switched on). Decoding of the periodic telemetric package is performed with special software (modem AX.25) which can be downloaded free of charge. The package structure is equipped with a check sum and other security features.
