Tyler Weaver / Mbed 2 deprecated Serial_interrupts_buffered

Dependencies:   buffered-serial1 mbed-rtos mbed

Fork of Serial_interrupts by jim hamblen

buffered_serial.cpp

Committer:
tylerjw
Date:
2012-12-10
Revision:
5:52705b8ccb32
Parent:
2:3d959c9fc9d7
Child:
6:ddab1e541812

File content as of revision 5:52705b8ccb32:

#include "buffered_serial.h"

BufferedSerial::BufferedSerial(PinName tx, PinName rx) : Serial(tx,rx), led1(LED1), led2(LED2), rx_sem(0), tx_sem(0)
{
    tx_in=0;
    tx_out=0;
    rx_in=0;
    rx_out=0;
    
    switch( _serial.index ) {
        case 0:
            device_irqn = UART0_IRQn;
            break;
        case 1:
            device_irqn = UART1_IRQn;
            break;
        case 2:
            device_irqn = UART2_IRQn;
            break;
        case 3:
            device_irqn = UART3_IRQn;
            break;
    }
    
    // attach the interrupts
    Serial::attach(this, &BufferedSerial::Rx_interrupt, Serial::RxIrq);
    Serial::attach(this, &BufferedSerial::Tx_interrupt, Serial::TxIrq);
}

// Copy tx line buffer to large tx buffer for tx interrupt routine
void BufferedSerial::send_line(char *c)
{
    int i;
    char temp_char;
    bool empty;
    i = 0;
    strncpy(tx_line,c,LINE_SIZE);
// Start Critical Section - don't interrupt while changing global buffer variables
    NVIC_DisableIRQ(device_irqn);
    empty = (tx_in == tx_out);
    while ((i==0) || (tx_line[i-1] != '\n')) {
// Wait if buffer full
        if (IS_TX_FULL) {
// End Critical Section - need to let interrupt routine empty buffer by sending
            NVIC_EnableIRQ(device_irqn);
            while (IS_TX_FULL) { // buffer is full
            }
// Start Critical Section - don't interrupt while changing global buffer variables
            NVIC_DisableIRQ(device_irqn);
        }
        tx_buffer[tx_in] = tx_line[i];
        i++;
        tx_in = NEXT(tx_in);
    }
    if (Serial::writeable() && (empty)) {
        temp_char = tx_buffer[tx_out];
        tx_out = NEXT(tx_out);
// Send first character to start tx interrupts, if stopped
        //Serial::putc(temp_char);
        LPC_UART1->THR = temp_char;
    }
// End Critical Section
    NVIC_EnableIRQ(device_irqn);
    return;
}

// Read a line from the large rx buffer from rx interrupt routine
void BufferedSerial::read_line(char *c)
{
    int i;
    i = 0;
// Start Critical Section - don't interrupt while changing global buffer variables
    NVIC_DisableIRQ(device_irqn);
// Loop reading rx buffer characters until end of line character
    while ((i==0) || (rx_line[i-1] != '\r')) {
// Wait if buffer empty
        if (rx_in == rx_out) {
// End Critical Section - need to allow rx interrupt to get new characters for buffer
            NVIC_EnableIRQ(device_irqn);
            while (rx_in == rx_out) {
            }
// Start Critical Section - don't interrupt while changing global buffer variables
            NVIC_DisableIRQ(device_irqn);
        }
        rx_line[i] = rx_buffer[rx_out];
        i++;
        rx_out = NEXT(rx_out);
    }
    rx_line[i-1] = 0;
// End Critical Section
    NVIC_EnableIRQ(device_irqn);
    strncpy(c,rx_line,LINE_SIZE);
    return;
}

// Interupt Routine to read in data from serial port
void BufferedSerial::Rx_interrupt()
{
    //uint32_t RBR = LPC_UART1->RBR;
    uint32_t IRR1 = LPC_UART1->IIR;
    led1=1;
// Loop just in case more than one character is in UART's receive FIFO buffer
// Stop if buffer full
    while (readable() || IS_RX_FULL) { 
        rx_buffer[rx_in] = LPC_UART1->RBR;
        //rx_buffer[rx_in] = Serial::getc();
        rx_in = NEXT(rx_in);
    }
    led1=0;
    return;
}

// Interupt Routine to write out data to serial port
void BufferedSerial::Tx_interrupt()
{
    //uint32_t RBR = LPC_UART1->RBR;
    uint32_t IRR = LPC_UART1->IIR;
    led2=1;
// Loop to fill more than one character in UART's transmit FIFO buffer
// Stop if buffer empty
    while ((writeable()) && (tx_in != tx_out)) { // while serial is writeable and there are still characters in the buffer
        //Serial::putc(tx_buffer[tx_out]);
        LPC_UART1->THR = tx_buffer[tx_out]; // send the character
        tx_out = NEXT(tx_out);
    }
    led2=0;
    return;
}