File content as of revision 9:45be5c5d5101:

//
//  iSerial.cpp ... Serial Driver with Interrupt Rec/Send
//
//  2009.11.13 ... Originally written by Y.Kuroda for Renesas H83664
//  2012.08.31 ... Code convert for mbed in C++
//  2015.01.02 ... Added other mbed code by JH1PJL
//

#include <stdarg.h>
#include "mbed.h"
#include "RingBuffer.h"
#include "iSerial.h"
// Device header files
#include "iSerial_LPC1768.h"
#include "iSerial_LPC11U24.h"
#include "iSerial_NucleoF4xx.h"
#include "iSerial_NucleoL152.h"

/*
 *    Interrupt Function
 */
void
iSerial::rx_handler(void)
{
    while(Serial::readable())
        rxbuf.save(Serial::getc());
}

void
iSerial::tx_handler(void)
{
    while(Serial::writeable() && txbuf.check())
        Serial::putc( txbuf.read() );
}

iSerial::iSerial(PinName _tx, PinName _rx, int _txbufsize, int _rxbufsize)
    :   Serial(_tx, _rx),
        tx(_tx),
        rx(_rx),
        txbufsize(_txbufsize),
        rxbufsize(_rxbufsize),
        txbuf(RingBuffer(txbufsize)),
        rxbuf(RingBuffer(rxbufsize)),
        str(new char [txbufsize])
{
    __disable_irq();

    attach(this, &iSerial::tx_handler, Serial::TxIrq);
    attach(this, &iSerial::rx_handler, Serial::RxIrq);

//  format(8,Serial::None,1);   // default
//  baud(baudrate);

    __enable_irq();
    enable_uart_irq();
}

iSerial::~iSerial()
{
    delete [] str;
}

int
iSerial::readable(void)
{
    return rxbuf.check();
}

int
iSerial::getc(void)
{
    unsigned short int c;

    while(!rxbuf.check());   // wait receiving a character
    disable_uart_irq();
    c = rxbuf.read();
    enable_uart_irq();

    return c;
}

void
iSerial::putc(short ch)
{
    if(txbuf.check()==0 && Serial::writeable()) {
        Serial::putc(ch);

    } else {
        while(txbuf.full()) {
            disable_uart_irq();
            tx_handler();
            enable_uart_irq();
        }

        disable_uart_irq();
        txbuf.save(ch);
        enable_uart_irq();
    }
}

short int
iSerial::putstr(const char* s)
{
    int i=0;
    for(; ; i++) {
        if(*s==0) break;
        putc(*s++);
    }
    return i;
}

short int
iSerial::puts(const char* s)
{
    short int n = putstr(s);
    putc(CR);
    putc(LF);
    return n;
}

char*
iSerial::printf(const char* format, ...)
{
    va_list arg;
    va_start(arg,format);
    vsprintf(str, format, arg);
    va_end(arg);
    putstr(str);
    return str;
}

void
iSerial::flush(void)
{
    while(txbuf.check())
        enable_uart_irq();
}