PICcoder - problem setting the EUART speed

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problem setting the EUART speed
Date: 2006/07/29 12:22	By: majestrix	Status: User
Karma: 0

Posts: 29

Hey guys,
I have been developing a USB application with a pic18f2550 and now i need to incoporate it with UART to communicate with an RF module. Here follows the piece of code i'm using to open my uart

OpenUSART (USART_TX_INT_OFF &
USART_RX_INT_ON &
USART_ASYNCH_MODE &
USART_EIGHT_BIT &
USART_CONT_RX &
USART_BRGH_HIGH, 129);

i'm using 129 as said in the page 243 of datasheet, since my oscillator is 20MHz, for a 9600 baud.
I'm just trying to send a string to the UART with putrsUSART("string");
the problem is I get some garbage characters on the display whn i test with hypertrminal.
my configuration settings as as follows.

oscillator: HSPLL - HS osc. PLL ena.
USB clk selection: USB clk. from 96 MHz PLL /2
sys clock postscaler: No postscaler
PLL Prescaler: Divided by 5 (20 MHz osc in.)

with these sattings my USB works. but UART is messed up as i said before..
so i changed my oscillator to an 8MHz crystal without changing anything else, just for a hunch.. well what do u know it works, but as expected USB dosent work.
So can someone please help me with this problem.
All i wanna do is use UART at a baud rate of 9600 along with USB.

thanks a lot.

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problem setting the EUART speed

majestrix

2006/07/29 12:22