Product 13/13

Setting up Optic Flow in INAV   PDF manual by Digitalentity



  • Optical Flow: PMW3901
  • Lidar: VL53L0X
  • Interface UART
  • Protocol: MSP
  • Working Range: 8cm~200cm
  • Field of view: 42 degree(PMW3901), 27 degree(VL53L0X)
  • Minimum Illumination >60Lux
  • Input voltage: 4.5~5.5V
  • Power Consumption: 40mA
  • Size: 36*12mm (F051 version),  2g
  • Size: 36*13mm (L051 version)  2g


  • Module 3901-L0X,  1pc


  • Make sure the Optical Flow lens to ground >2cm for opflow initialization while FC starting up.
  • The maximum range of VL53L0X is 2m,   Altitude hold 0~2m @ throttle 0~100% if VL53L0X is enabled.
  • Any unused UART of FC supports it
  • Sonar connection (Trig & Echo) has not been implemented
  • If your flight controller doesn’t have a barometer detected, you won’t be able to select “NAV ALTHOLD” in the modes tab.


ArduPilot's latest firmware has supported MSP protocol since Sep.02

  • SERIALn_PROTOCOL = 32,  “n” is the serial number of UART in ArduPilot hwdef, not the FC UART number.  On some flight controllers, serial1 is not equal to UART1, Pls checkout the FC manual to get the corresponding serial number for each UART.
  • SERIAL_BAUD = 115
  • RNGFND_TYPE = 32
  • FLOW_TYPE = 7

Communication between 3901-L0X module and Flight controller via UART MSP V2 protocol supported by INAV and ArduPilot.

There is no detailed datasheet of the MSP V2 protocol.

Please refer to the code in INAV and ArduPilot Github


Product SKU: 4994-127

  • Brand: Matek Systems
Status : Available in Stock

Current Reviews: 0