Hcsr04

tanuagg13

Hi,

I'm having trouble getting my HC-SR04 ultrasonic sensor to work properly. It works perfectly for distances larger than 4-5 cm, but I need it to work right up to its tolerance level of 0.2 cm.

This is a 4-pin module, and I have directly wired Vcc and Gnd pins to Vdd and Vss. Trigger and echo are directly wired to pins 0 and 1.

Here is my code.

' {$STAMP BS2}
' {$PBASIC 2.5}




time VAR Word
distance VAR Word


OUTPUT 0
INPUT 1


DO


 PULSOUT 0, 5
 PULSIN 1, 1, time
 distance = time ** 22510
 DEBUG CR, "Distance = ", DEC distance/10,".",DEC2 distance," cm"


LOOP

Basically, what's happening is that if I go below 2-3 cm in distance to the sensor, the sensor readings go to 4,5,6 cm and then eventually drop directly to 0.00 cm.

Hal Albach

All the HC_SR04 data sheets I looked up state a minimum distance of 2 cm and a resolution of .3 cm. Perhaps you can provide a link to the datasheet for a unit that has a minimum distance of 0.2 cm.

goleagt

Hello I am super new, is there a wiring diagram of how to connect HC-SR04 to the boe bot? Any help would be great

Hal Albach

If you look at the first post above you will see that he has the trigger connected to Pin 0 and Echo to Pin 1. Also connect ground and +5 to the device. Use the program in Post 1 to start.