source: trunk/software/firmware/serial2.c

#include <pic18fregs.h>
#include <stdio.h>
#include <my_serial2.h>

char uart2_txbuf[UART2_BUFSIZE];
unsigned char uart2_txbuf_prod;
volatile unsigned char uart2_txbuf_cons;

char uart2_rxbuf[UART2_BUFSIZE];
volatile unsigned char uart2_rxbuf_prod;
unsigned char uart2_rxbuf_cons;

void
uart2_putchar_raw(char c)
{
        unsigned char new_uart2_txbuf_prod;
        new_uart2_txbuf_prod = (uart2_txbuf_prod + 1) & UART2_BUFSIZE_MASK;
        while (new_uart2_txbuf_prod == uart2_txbuf_cons) {
                PIE3bits.TX2IE = 1; /* ensure we'll make progress */
        }
        uart2_txbuf[uart2_txbuf_prod] = c;
        uart2_txbuf_prod = new_uart2_txbuf_prod;
        PIE3bits.TX2IE = 1;
}

char
uart2_getchar()
{
        register char c;
        while (uart2_rxbuf_cons == uart2_rxbuf_prod)
                ;

        uart2_rxbuf_cons = (uart2_rxbuf_cons + 1) & UART2_BUFSIZE_MASK;
        c = uart2_rxbuf[uart2_rxbuf_cons];
        return c;
}