PIC TO PIC COMUNICATION

ccmcca · Joined: 08 Oct 2005 Posts: 13

How can i send a variable from one pic to another?
Is rs232 or I2C the better method?
I need an example.
Thanks!!.-

kender · Joined: 09 Aug 2004 Posts: 768 Location: Silicon Valley

It depends on the length of your transmission line (in meters), on your desired data rate and directionality of your communication, your constraints such as power consumprion, board size, EMI (including galvanic isolation) and - finally - cost. Tell us more about your application.

Here are a few typical cases (in no particular order):

* A "master controller" and secondary controller(s) on the same board (or at least in the same box without a lot of EMI). I would recommend I2C. Most PICs have a hardware I2C protocol engine, plus I2C doesn't require bus transceivers. There is code for I2C master and I2C slave in this forum.

* Pier-to pier network. Take a look at Controller Area Network (CAN). Again, there is code for CAN comunication in the forum and in the examples. However, CAN requires bus transcievers.

rwyoung · Joined: 12 Nov 2003 Posts: 563 Location: Lawrence, KS USA

Guest · Posted: Sat Oct 29, 2005 4:16 pm

I have the two chips in the same board.
this is the code

receiver

#include "mainbalanza.h"
#int_RDA
RDA_isr()
{
printf(LCD_PUTC,"DEBUG";
}
void main()
{
ini();

while(1)
{

}
}

sender

#include "USvar16f627.h"
void main()
{
while(true)
{
printf("%S\n\r","16f627";
}

}

dyeatman · Joined: 06 Sep 2003 Posts: 1924 Location: Norman, OK

Read the CCS FAQ. It has an example and tells you what CCS example code you can use to implement the example.

Ttelmah · Guest

Also look at the threads here, about interrupts, and serial interrupts in particular.
Your receive interrupt _must_ retrieve the character, or it'll sit in a permanent loop, since it'll keep retriggering waiting for the character to be accepted. You are sending 8 characters, and never retrieving any...

Best Wishes