Sonar
A sonar sensor can be used to measure altitude for use with BARO and SONAR altitude hold modes.
The sonar sensor is used instead of the pressure sensor (barometer) at low altitudes (less than about 3.5 meters above the ground). The sonar sensor is only used when the aircraft inclination angle (attitude) is small (less than 22.5 degrees).
Hardware
Currently the only supported sensor is the HCSR04 sensor.
Connections
Naze/Flip32+
Mode | Trigger | Echo | Inline 1k resistors |
---|---|---|---|
Parallel PWM/ADC current sensor | PB8 / Motor 5 | PB9 / Motor 6 | NO (5v tolerant) |
PPM/Serial RX | PB0 / RC7 | PB1 / RC8 | YES (3.3v input) |
Constraints
Current meter cannot be used in conjunction with Parallel PWM and Sonar.
Olimexino
Trigger | Echo | Inline 1k resistors |
---|---|---|
PB0 / RC7 | PB1 / RC8 | YES (3.3v input) |
Constraints
Current meter cannot be used in conjunction with Sonar.
CC3D
Trigger | Echo | Inline 1k resistors |
---|---|---|
PB5 / RC4 | PB0 / RC5 | YES (3.3v input) |
Constraints
Sonar cannot be used in conjuction with SoftSerial or Parallel PWM.
SPRacingF3
Trigger | Echo | Inline 1k resistors |
---|---|---|
PB0 / RC7 | PB1 / RC8 | YES (3.3v input) |
Constraints
Sonar cannot be used in conjuction with SoftSerial2 or Parallel PWM.