garbage input with rs232 bluetooth but perfect output

ist worker · Guest

Compiler version: 3.245
Pic version: 18F8722

Here a short description of a problem that has really been frustrating me, and its doubly frustrating since I fixed it in the past, but don't remember how now. Also ive searched the forum thoroughly for insight into this problem and havent found an answer, but in case i am rehashing a common topic, i do apologize.

I am able to communicate with the pic using a bluetooth connection, but input is getting garbled, while communication originating from the pic comes through clearly. I tested this by just echoing input back out, as well as following that by putc'ing another character. So when i send the pic something i get garbage output, sometimes random, most times "<0>" , and that is followed by the putc character.

I know hardware is not an issue here, since the same pic has been loaded with working firmware and tested.

Im going to post my code, and i really appreciate if someone could help me shed some light on this. My own intuition tells me it has something to do with fuses, because i know little to nothing about what they do. Thanks!!

Wayne_ · Joined: 10 Oct 2007 Posts: 681

Most likely something to do with the pic going to sleep after init() in main.

Try putting

while(true) {
}

after init().
This will prevent the pic going to sleep.

No gaurantees with this though!

Guest · Posted: Thu Mar 27, 2008 9:49 am

thanks wayne, actually i did have a while loop in there just looping forever with nothing in it, i didnt think it was necessary, but with it in the same problem still applies.

Wayne_ · Joined: 10 Oct 2007 Posts: 681

because you are not using fast_io those set_tris statements mean nothing.
They should be done before the enable ints anyway.

Just remove them unless you plan on using fast_io!

ist worker · Guest

thanks again, i forgot to put my name in my last post btw.

I put those set_tris statements in to see if it would remedy my problem, but with those statements removed, i still have the same problem.

ist worker · Guest

Wow ok, the problem has been solved, thank goodness.

I was powering the PIC circuit board through the ICD-U40 thingy plugged into the usb port rather than through the battery pack. The EE i work with pointed out that it may not be enough power to run bluetooth, and he was right! Using the correct power source solved the problem.