uart.h

Program for implementing AES on 8051 based microcontrollers. SDCC is used as the C compiler. Microco

// UART functions for SDCC / P89V51RD2

/* Original Code by:
 * Author	: Chin-Shiuh Shieh (http://bit.kuas.edu.tw/~csshieh/)
 * Date		: 2001-01-01 (yyyy-mm-dd)
 */
 
/* Modified for ucmicrosys UNI-51-SDK (www.ucmicrosys.com) by
 * Author(s)	: Anurag Chugh ([e-mail]) and Ranjit Puri ([e-mail])
 * Date		: 2006-12-15 (yyyy-mm-dd)
 */

//NOTES:
//1: This code may be distributed and modified freely. 
//2: uart_init() should be called before using UART. It is used to initialise the SFRs
//3: No syntax error handling is performed by the functions.
//4: Comment un-used functions to reduce code size.
//5: External Crystal of 11.0592 MHz is assumed.
//6: UART parameters are pre-set to 9600 bps 8-N-1

#ifndef __p89v51rd2_h__
	#include <p89v51rd2.h>
	#define __p89v51rd2_h__
#endif

// UART function protoypes
void uart_init(void);		// Set UART Baud Rate to 9600 bps.
void uart_putc(char c);		// Put Character to UART.
char uart_getc(void);		// Get Character from UART.
char uart_getce(void);		// Get Character from UART with Echo, Requires uart_putc().
void uart_puts(char *s);	// Put String to UART, Requires uart_putc().
void uart_gets(char *s);	// Get String from UART, Requires uart_getce().
void i2s(int i,char *s);	// Convert Interger to String.
int s2i(char *s);		// Convert String to Integer.
void uart_puti(int i);		// Put Integer to UART, Requires i2s() & uart_puts().
int uart_geti();		// Get Integer from UART, Requires uart_gets() & s2i().

void uart_init(void)
{
_asm
	anl		PCON,#0x7F	// Clear SMOD of PCON, No Double Baud Rate.
	anl		TMOD,#0xAF	// Clear C/T, M0 for Timer1 of TMOD.
	orl		TMOD,#0x20	// Set M1 for Timer1 of TMOD.
						// Set Timer1 to Mode 2 (8-bit auto reload) for Baud Rate Generation.
	mov		TH1,#0xFD	// Set Baud Rate to 9600 bps.
	clr		SM0			// Clear SM0 of SCON.
	setb	SM1			// Set SM1 of SCON.
						// Set UART to Mode 1 (8-bit UART).
	setb	REN			// Set REN of SCON to Enable UART Receive.
	setb	TR1			// Set TR1 of TCON to Start Timer1.
	setb	TI			// Set TI of SCON to Get Ready to Send.
	clr		RI			// Clear RI of SCON to Get Ready to Receive.
_endasm;
}

void uart_putc(char c)	// Put Character to UART.
{
	while(TI==0);
	TI=0;
	SBUF=c;
}

char uart_getc(void)	// Get Character from UART.
{
	while(RI==0);
	RI=0;
	return SBUF;
}

char uart_getce(void)	// Get Character from UART with Echo, (calls uart_putc()).
{
	while(RI==0);
	RI=0;
	uart_putc(SBUF);
	return SBUF;
}

void uart_puts(char *s)	// Put String to UART, (calls uart_putc()).
{
	while(*s!=0)
	{
		uart_putc(*s);
		s++;
	}
}

void uart_gets(char *s)	// Get String from UART, (calls uart_getce()).
{
	while(((*s)=uart_getce())!=13)
	{
		s++;
	}
	*s=0;
}

void i2s(int i,char *s)	// Convert Interger to String.
{
	char sign;
	short len;
	char *p;
	
	sign='+';
	len=0;
	p=s;
	
	if(i<0)
	{
		sign='-';
		i=-i;
	}
	
	do
	{
		*s=(i%10)+'0';
		s++;
		len++;
		i/=10;
	}while(i!=0);
	
	if(sign=='-')
	{
		*s='-';
		s++;
		len++;
	}
	
	for(i=0;i<len/2;i++)
	{
		p[len]=p[i];
		p[i]=p[len-1-i];
		p[len-1-i]=p[len];
	}
	
	p[len]=0;
}

int s2i(char *s)		// Convert String to Integer.
{
	int i=0;
	char sign='+';
	
	if(*s=='-')
	{
		sign='-';
		s++;
	}
	
	while(*s!=0)
	{
		i=i*10+(*s-'0');
		s++;
	}
	
	if(sign=='-')
	{
		i=-i;
	}
	
	return i;
}

void uart_puti(int i)		// Put Integer to UART, (calls i2s() & uart_puts()).
{
	char s[7];
	i2s(i,s);
	uart_puts(s);
}

int uart_geti()			// Get Integer from UART, (calls uart_gets() & s2i()).
{
	char s[7];
	uart_gets(s);
	return s2i(s);
}