Waterproof JSN-SR04T Ultrasonic Distance Sensor

The JSN-SR04T is an ultrasonic distance sensor. There are two versions v2.0 and v3.0. They differ in the range of action. v2.0 with a range of 25 to 450 cm. v3.0 with a range of 20 to 600 cm. Also more stable. The very short range makes it of limited use.

../_images/JSN-SR04TV2.jpg ../_images/JSN-SR04TV3.jpg ../_images/JSN-SR04T.jpg

Connection to the autopilot

To setup as the first rangefinder. Reboot after setting parameters:

  • RNGFND1_MAX_CM = “450” (i.e. 4.5m max range for v2.0 ver)
  • RNGFND1_MIN_CM = “25” (i.e. 25cm min range for v2.0 ver)
  • RNGFND1_STOP_PIN = Enter GPIO number for pin attached to JSN-SR04T “Trigger” pin. For example, on PixHawk with BRD_PWM_COUNT = 4, AUX6 (GPIO 55) could be used here, and AUX5 (GPIO54) could be used below.
  • RNGFND1_PIN = Enter GPIO number for pin attached to JSN-SR04T “Echo” pin.
  • RNGFND1_TYPE = “30” (HC-SR04 sonar)
  • RNGFND1_ORIENT = “25” (Downward facing) if used for altitude control.