Urgent: Communicating PIC to PC

[chava]

Hello
I have a PICDEM2 PLUSE board in my house and I connected it to the PC.
I assembled a PIC16f877a on the PICDEM2 PLUSE and wrote a simple program to send data to the PC via the RS232 connector (which is on the picdem2 pluse board).
BUT every time I activate the pic program, the PC stops to respond and I have to reboot it
note:

1. what I did is - I placed the PIC on another board and connected only the lines related to the Power supply, MCLR, RS232 communication and the LCD to the picdem2pluse.
then I saw that I connected C5,C6 instead of C6, C7 ( on both connctions, the PIC transmitted to the PC when the hyper terminal works).
I fixed it but nothing changed.

2. I run the pic when the hyper terminal is active - and it works good. when the hyper terminal is not connected, the pc stops to respond the minute I press "debugger --> run "(in the mplab menue)

3. I once did activated the pic that way and I succeeded to make the communication but it was with a nother pic program


Does any of you have a clue - what is the problem? why the PC stops to respond (nothing works, no mouse, no keyboard, no respond to ctrl+alt+del )
what may be the problem?


Jukin Chava
E2D
Electronic Embedded Development

[SherpaDoug]

Are you running Hyperterminal on the same PC as the debugger?

A couple of suggestions in order of preference:
1) Find a "dumb terminal" to view the serial output instead of a PC.
2) Don't use Hyperterminal, it sucks. Instead use SIO that comes with the compiler or better yet "terminal" which can be found at:
http://bray.velenje.cx/avr/terminal
3) Close the debugger while running whichever terminal program you choose.
_________________
The search for better is endless. Instead simply find very good and get the job done.

[PCM programmer]

Post a very short program that demonstrates the problem.
Strip out all unessential code, and leave in only the code that
causes the problem. Also, post all pre-processor statements
in your program, such as #use delay, #fuses, ICD=TRUE, etc.

Tell us what debugger you are using. That's the key to the
whole problem. It's not "PIC can't talk to PC", it's more like
"My ICD2 locks up my PC when I run my program. Help,
I have an ICD2 problem".

So, we need the full truth, to work on it for you.

Also, you should update all the software that you are using.
Update MPLAB. Update the internal ICD2 firmware, etc.

[chava]

Hi, Tanks for the reply
I use PCM 3.178
MPLAB 6.
ICD2
PICDEM2 PLUSE board
win xp- home edition

when I add the lines: "putc('p');
puts("string to pc");"
and activate the program (running the mplab under debugging ICD2)
the PC stops to respond (no respond to mouse, no keyboard, no alt+ctrl+del, not even an error message from windows to inform me that a program was endded due to an unautorized action.)

I did that when the Hyper terminal is active and I saw the data ("pstring to pc" on the hyper terminals' window.the pc didnt stop to respond when the hyper terminal was active.
I thougth that it may have something to do with the RS232 bufer been full... or something like that.

here is the code

[PCM programmer]

I think the problem must either be in your O/S or in MPLAB/ICD2.
You didn't give your exact version of MPLAB.

I think the best course of action is to install the latest version of MPLAB,
and then install the latest ICD2 firmware (which comes with MPLAB).

[PCM programmer]

What version of MPLAB are you using ?

We have a Win2K system at our company, and we tried to
use ICD2 and MPLAB 6.42 on it. It acted in a very flakey way.
It would lock up, and the mouse would stop working.
This was just during normal debugging. We were not trying
to use the serial port for communications, as you were doing.

We un-installed MPLAB vs. 6.42, and installed vs. 6.40, and
it seems to be much more stable. Since Win2K is similar
to XP, I suggest that you try this.

[chava]

tanks, Ill try
jukingh@zahav.net.il