Troubleshooting Connectivity - ShikOfTheRa/scarab-osd GitHub Wiki

This is a guide to help troubleshoot connectivity issues with Flight Controllers.

Step 0 - check the wiring (Device = PC, FC or GPS)

  • OSD TX > Device RX (usually)
  • OSD RX > Device TX (usually)

Step 1 - flash OSD with

  • device = utilities
  • Variant = debug
  • Type = 115kMSP (for FC with serial MSP Betaflight/iNAV etc.)

Step 2a - test from PC GUI (MSP based flight controllers)

  • select correct PC com port
  • select 115k speed
  • click connect
  • if values for RX and PKT are not zero, this indicates OSD is working

Step 2b - test from PC GUI (MAVLINK based flight controllers)

Step 3 - test with FC or GPS connected

  • if BOTH values for BOTH RX and PKT are not zero, this indicates OSD is receiving valid data
  • if either values for RX or PKT are displaying zero, this indicates OSD is not receiving valid data.

Troubleshooting : RX - count of RX data receive per second.

  • A non zero value here means data is being received from connected device such as Flight Controller or GPS.
  • This usually means the cabling is correct although watch for two things connected at same time.
  • Only one tx line can be connected to one or more rx lines at same time.
  • For MAVLINK based FC, ensure FC port is configured correctly for OSD
  • Some clones have incorrect labelling. RX/TX labelling is reversed.
  • It does not mean it is the correct baud rate or that data is valid.
  • Use this value simply to verify that it is connected and receiving data.

Troubleshooting : PKT - count of valid packets of data received per second.

  • A non zero value means that the OSD is receiving valid data packets.
  • This usually means everything is working correctly.
  • It does not mean it is receiving all the information required for all features.

DEBUG display parameters

  • RC - RC channels PPM Value. 1500 means probably not receiving any data.
  • ANAL - Analog input values in order of BAT1/BAT2/AMPS/RSSI/TEMP.
  • PWM - PWM input values in order of RSSI / AEROMAX OSD PPM input.
  • D0-D4 - Developer value - test values.
  • SAT - Number of satellites received.
  • ARM - Armed status.
  • Loop - Number of times the OSD runs its routines per second.
  • RX - Number of bytes received on serial port per second.
  • PKT - Number of valid data packets of data received per second.
  • MEM - Developer value - amount of free volatile memory available. Not Program memory.