Collecting stream height via an ultrasonic sensor connected to a BeagleBone Black and communicating it to web server

Sensor sampling

Environment variables that are used to define valid sampling ranges for the sensor, and to make sure the correct sensor is setup.

• GAGE_SERIAL_PORT - Serial Port dev path of sensor to sample (default '/dev/ttyS2')
• GAGE_SERIAL_UART - Serial Port UART name of sensor (default 'UART2')
• GAGE_STORAGE_MOUNT_PATH - Path to where the µSD card will be mounted (defaults to '/mnt/gagedata', currently shouldn't be changed)
• GAGE_DATA_CSV_FOLDER - Folder where logger data should be stored (default '/mnt/gagedata/logs/'.
• GAGE_FILE_LOG_FOLDER - Folder where system logs should be stored in a rotating file '/mnt/gagedata/syslogs/'.
• GAGE_MAX_LOG_FILES - Maximum number of rotating log files that should be stored (default 10).
• GAGE_SAMPLE_WAIT - Time to wait between collecting each sample (in seconds, default 5)
• GAGE_MIN_VOLTAGE - If the battery is below the voltage, the gage will power off early and sleep for GAGE_MIN_VOLTAGE_RESTART_TIME (Default 3.0).
• GAGE_CELL_TYPE
• GAGE_SAMPLES_PER_RUN
• GAGE_PRE_SHUTDOWN_TIME
• GAGE_MAX_UPDATE_WAIT
• GAGE_SENSOR_LOW - Lowest valid value from the sensor (default 501 for using Maxbotix MB7386)
• GAGE_SENSOR_HIGH - Highest valid value from the sensor (default 9998 for using Maxbotix MB7386)
• GAGE_MIN_SAMPLES
• GAGE_MAX_ATTEMPTS
• GAGE_MAX_STD_DEV

Power control

Environment variables that control how long the gage is on and off as it goes through the day. Mostly used to control the AndiceLabs Power Cape. Power Cape watchdog information

• GAGE_POWER_CONSERVE - Should the gage shut down and go into power conservation mode between sampling sets
• GAGE_RESTART_TIME
• GAGE_MIN_VOLTAGE_RESTART_TIME
• GAGE_WATCHDOG_RESET_TIMEOUT
• GAGE_WATCHDOG_POWER_TIMEOUT
• GAGE_WATCHDOG_STOP_POWER_TIMEOUT
• GAGE_WATCHDOG_START_POWER_TIMEOUT
• GAGE_STARTUP_REASONS