# DISTANCE()

Compatible with:
DOS Maximite CMM MM150 MM170 MM+ MMX Picromite ArmiteL4 Armite F4 ArmiteH7 Picomite CMM2

Syntax:
DISTANCE( trigger [, echo ] )
DISTANCE( trig-echo )

Description:
Measure the distance to a target using the HC-SR04 ultrasonic distance sensor.
Four pin sensors have separate trigger and echo connections. 'trigger' is the I/O pin connected to the "trig" input of the sensor and 'echo' is the pin connected to the "echo" output of the sensor.
Three pin sensors have a combined trigger and echo connection and in that case you only need to specify one I/O pin to interface to the sensor.
Note that any I/O pins used with the HC-SR04 should be 5V capable as the HC-SR04 is a 5V device.
The I/O pins are automatically configured by this function and multiple sensors can be used on different I/O pins.
The value returned is the distance in centimetres to the target or -1 if no target was detected or -2 if there was an error (ie, sensor not connected).

Last edited: 29 September, 2020