/*
  Jesper Hansen <jesperh@telia.com>
  
  Original Author: Volker Oth <volkeroth@gmx.de>
  
  This file is part of the yampp system.

  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License
  as published by the Free Software Foundation; either version 2
  of the License, or (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software Foundation, 
  Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/


#include <io.h>
#include <interrupt.h>
#include <signal.h>
#include <progmem.h>
#include "uart.h"

/* UART global variables */
volatile u08   UART_Ready;
volatile u08   UART_ReceivedChar;
         u08   UART_RxChar;
         u08*  pUART_Buffer;

/* end-of-line string = 'Line End' + 'Line Feed' character */
prog_char UART_pszEndOfLine[3] = {0x0d,0x0a,0};

/* UART Transmit Complete Interrupt Function */
SIGNAL(SIG_UART_TRANS)      
{
    /* Test if a string is being sent */
    if (pUART_Buffer!=0)
    {
        /* Go to next character in string */
        pUART_Buffer++;
        /* Test if the end of string has been reached */
        if (PRG_RDB(pUART_Buffer)==0)
        {
            /* String has been sent */
            pUART_Buffer = 0;
            /* Indicate that the UART is now ready to send */
            UART_Ready   = 1;
            return;
        }
        /* Send next character in string */
        outp( PRG_RDB(pUART_Buffer), UDR );
        return;
    }
    /* Indicate that the UART is now ready to send */
    UART_Ready = 1;
}

/* UART Receive Complete Interrupt Function */
SIGNAL(SIG_UART_RECV)      
{
    /* Indicate that the UART has received a character */
    UART_ReceivedChar = 1;
    /* Store received character */
    UART_RxChar = inp(UDR);
}

void UART_SendByte(u08 Data)
{   
    /* wait for UART to become available */
    while(!UART_Ready);
    UART_Ready = 0;
    /* Send character */
    outp( Data, UDR );
}

u08 UART_ReceiveByte(void)
{
    /* wait for UART to indicate that a character has been received */
    while(!UART_ReceivedChar);
    UART_ReceivedChar = 0;
    /* read byte from UART data buffer */
    return UART_RxChar;
}

void UART_PrintfProgStr(u08* pBuf)
{
    /* wait for UART to become available */
    while(!UART_Ready);
    UART_Ready = 0;
    /* Indicate to ISR the string to be sent */
    pUART_Buffer = pBuf;
    /* Send first character */
    outp( PRG_RDB(pUART_Buffer), UDR );
}

void UART_PrintfEndOfLine(void)
{
    /* wait for UART to become available */
    while(!UART_Ready);
    UART_Ready = 0;
    /* Indicate to ISR the string to be sent */
    pUART_Buffer = UART_pszEndOfLine;
    /* Send first character */
    outp( PRG_RDB(pUART_Buffer), UDR );
}

void UART_PrintfU4(u08 Data)
{
    /* Send 4-bit hex value */
    u08 Character = Data&0x0f;
    if (Character>9)
    {
        Character+='A'-10;
    }
    else
    {
        Character+='0';
    }
    UART_SendByte(Character);
}

void UART_Printfu08(u08 Data)
{
    /* Send 8-bit hex value */
    UART_PrintfU4(Data>>4);
    UART_PrintfU4(Data);
}

void UART_Printfu16(u16 Data)
{
    /* Send 16-bit hex value */
    UART_Printfu08(Data>>8);
    UART_Printfu08(Data);
}

void UART_Printfu32(u32 Data)
{
    /* Send 32-bit hex value */
    UART_Printfu16(Data>>16);
    UART_Printfu16(Data);
}

void UART_Init(void)
{
    UART_Ready        = 1;
    UART_ReceivedChar = 0;
    pUART_Buffer      = 0;
    /* enable RxD/TxD and interrupts */
    outp(BV(RXCIE)|BV(TXCIE)|BV(RXEN)|BV(TXEN),UCR);
    /* set baud rate */
    outp( (u08)UART_BAUD_SELECT, UBRR);  
    /* enable interrupts */
    sei();
}

unsigned char UART_HasChar(void)
{
	return UART_ReceivedChar;
}


void UART_Puts(u08* pBuf)
{
	while (*pBuf)
		UART_SendByte(*pBuf++);
}

void UART_Putsln(u08* pBuf)
{
	UART_Puts(pBuf);
	UART_PrintfEndOfLine();
}


/*
// Print a number in the given base 

void print_number (int base, int unsigned_p, long n)
{
  	static char chars[16] = "0123456789abcdef";
  	char *p, buf[32];
  	unsigned long x;

  	if (!unsigned_p && n < 0)
    {
      	UART_SendByte('-');
      	x = -n;
    }
  	else
    	x = n;

  	p = buf + sizeof (buf);
  	*--p = '\0';
  	do
    {
      	*--p = chars[x % base];
      	x /= base;
    }
  	while (x != 0);

	while (*p)
		UART_SendByte(*p++);
}

*/