[Kevin Watson]

Originally Posted by wt200999

I wrote a program to run this sensor (Parallax PING))) ) for ports 1&2, and it worked fine, but I decided I would rather have them on ports 3-6 and have 1&2 for my encoders, so I re-wrote my code, and now it doesn't work properly. I end up getting one high number when I first turn on the robot, then a steady number of 35 for the distance and 25 for the time. Here is my code:

http://www.easternfront.org/ultrasonic_port_3_6.zip

I had several printf's spread around in it to see if I was getting to all of the places in my code, thats what that phasetest is. My implementation of it in the default routine is:

if(x==1)
{
    Ping(3);
}
 
if(x==20)
{
     printf("Distance:%d Time%d\r",Get_Distance(3),Ultrasonic_3_Time);
     x=0;
}
x++;

Any help would be greatly appreciated, thank you.

I had a quick look at your code and found what I think are a few errors. Have a look at the attached file for my comments (search on "RKW").

-Kevin

Edit: It looks like you're driving the sensor with a digital I/O pin and then using a separate interrupt pin to time the pulse. I had assumed you were doing both from one pin, so you can ignore my comment about the TRISB register.