PIC16f1527 UART1 Declaration problem

[ragav4456]

Hello sir
I Have doubt in PIC16f1527 IC UART1.

How to select UART1 and how to configure uart1 bits?

 

[jayanth.devarayanadurga]

Which Compiler are you using?

 

[ragav4456]

MPLAB Hitech C compiler

 

[Tahmid]

Here are the steps (from the datasheet: https://ww1.microchip.com/downloads/en/DeviceDoc/41458B.pdf):

Hope this helps.
Tahmid.

 

[jayanth.devarayanadurga]

For UART1 registers are

SP1BRGL
SP1BRGH
TX1REG
TX1STA
RC1STA


For UART2 registers are

SP2BRGL
SP2BRGH
TX2REG
TX2STA
RC2STA

For 9800 Baud 8 bit transmission No parity, 1 stop bits

TX1STA
CSRC = 0 or 1 Asyncronous Mode
TX9 = 0 8 bit Tx
TXEN = 1 Transmit is enabled
SYNC = 0 Asynchronous mode
SENDB = 1
BRGH = 0 for low speed
1 for hign speed
TRMT = 1 empty
TX9D = 0 or 1 Async mode

RC1STA
SPEN = 1
RX9 = 0
SREN = 0 or 1 Ascyn mode
CREN = 1 enable receiver
ADDEN = 0
FERR = 0
OERR = 0
RX9D = 0 or 1 Async mode

 

[ragav4456]

Thanks,
I am using Hi-tech c compiler. Embedded c

TX1STAbits.SYNC = 0; // Correct or Not..?

 

[jayanth.devarayanadurga]

If you are using Asynchronous mode then SYNC = 0 is right.

 

[ragav4456]

Ya Iam using Asynchronous mode. Configure format?


what is the difference between 16f877 IC and 16f1527 IC UART function?

 

[jayanth.devarayanadurga]

I don't know the difference as I haven't seen the datasheet. I think the only difference is the later has 2 UART. Usually the working of UART will be the same.
What configure format do you want?

 

[ragav4456]

how to declare UART1 selection bits? // How to declare SPEN bit?

SPEN=1; // error;

 

[jayanth.devarayanadurga]

There is no SPEN bit. It is only needed for UART Initialization. If SPEN is not in your PIC then don't implement it.

 

[ragav4456]

Check the datasheet. SPEN bit is available.

 

[Tahmid]

how to declare UART1 selection bits? // How to declare SPEN bit?

SPEN=1; // error;

There are 2 SPEN bits in 16F1527 - one for UART1 and another for UART2.

Can you upload the header file for 16F1527?

Without looking at the header file, I can't say what you need to write, at least not with certainty.

You may try:

SPEN1 = 1;

or

SP1EN = 1;

Hope this helps.
Tahmid.

 

[ragav4456]

SP1EN = 1; is undefined identifier.

pic16f1527.h

#ifndef _HTC_H_
#warning Header file pic16f1527.h included directly. Use #include <htc.h> instead.
#endif

/* header file for the MICROCHIP PIC microcontroller
* 16F1527
*/


#ifndef __PIC16F1527_H
#define __PIC16F1527_H

//
// Configuration mask definitions
//


// Config Register: CONFIG1
#define CONFIG1 0x8007
// Oscillator Selection
// ECH, External Clock, High Power Mode (4-20 MHz): device clock supplied to CLKIN pin
#define FOSC_ECH 0xFFFF
// ECM, External Clock, Medium Power Mode (0.5-4 MHz): device clock supplied to CLKIN pin
#define FOSC_ECM 0xFFFE
// ECL, External Clock, Low Power Mode (0-0.5 MHz): device clock supplied to CLKIN pin
#define FOSC_ECL 0xFFFD
// INTOSC oscillator: I/O function on CLKIN pin
#define FOSC_INTOSC 0xFFFC
// EXTRC oscillator: External RC circuit connected to CLKIN pin
#define FOSC_EXTRC 0xFFFB
// HS Oscillator, High-speed crystal/resonator connected between OSC1 and OSC2 pins
#define FOSC_HS 0xFFFA
// XT Oscillator, Crystal/resonator connected between OSC1 and OSC2 pins
#define FOSC_XT 0xFFF9
// LP Oscillator, Low-power crystal connected between OSC1 and OSC2 pins
#define FOSC_LP 0xFFF8
// Watchdog Timer Enable
// WDT enabled
#define WDTE_ON 0xFFFF
// WDT enabled while running and disabled in Sleep
#define WDTE_NSLEEP 0xFFF7
// WDT controlled by the SWDTEN bit in the WDTCON register
#define WDTE_SWDTEN 0xFFEF
// WDT disabled
#define WDTE_OFF 0xFFE7
// Power-up Timer Enable
// PWRT disabled
#define PWRTE_OFF 0xFFFF
// PWRT enabled
#define PWRTE_ON 0xFFDF
// MCLR Pin Function Select
// MCLR/VPP pin function is MCLR
#define MCLRE_ON 0xFFFF
// MCLR/VPP pin function is digital input
#define MCLRE_OFF 0xFFBF
// Flash Program Memory Code Protection
// Program memory code protection is disabled
#define CP_OFF 0xFFFF
// Program memory code protection is enabled
#define CP_ON 0xFF7F
// Brown-out Reset Enable
// Brown-out Reset enabled
#define BOREN_ON 0xFFFF
// Brown-out Reset enabled while running and disabled in Sleep
#define BOREN_NSLEEP 0xFDFF
// Brown-out Reset controlled by the SBOREN bit in the BORCON register
#define BOREN_SBODEN 0xFBFF
// Brown-out Reset disabled
#define BOREN_OFF 0xF9FF
// Clock Out Enable
// CLKOUT function is disabled. I/O or oscillator function on the CLKOUT pin
#define CLKOUTEN_OFF 0xFFFF
// CLKOUT function is enabled on the CLKOUT pin
#define CLKOUTEN_ON 0xF7FF
// Internal/External Switchover
// Internal/External Switchover mode is enabled
#define IESO_ON 0xFFFF
// Internal/External Switchover mode is disabled
#define IESO_OFF 0xEFFF
// Fail-Safe Clock Monitor Enable
// Fail-Safe Clock Monitor is enabled
#define FCMEN_ON 0xFFFF
// Fail-Safe Clock Monitor is disabled
#define FCMEN_OFF 0xDFFF


// Config Register: CONFIG2
#define CONFIG2 0x8008
// Flash Memory Self-Write Protection
// Write protection off
#define WRT_OFF 0xFFFF
// 000h to 1FFh write protected, 200h to 3FFFh may be modified by PMCON control
#define WRT_BOOT 0xFFFE
// 000h to FFFh write protected, 2000h to 3FFFh may be modified by PMCON control
#define WRT_HALF 0xFFFD
// 000h to 3FFFh write protected, no addresses may be modified by PMCON control
#define WRT_ALL 0xFFFC
// Voltage Regulator Capacitor Enable bit
// VCAP pin function disabled
#define VCAPEN_OFF 0xFFFF
// VCAP pin function enabled
#define VCAPEN_ON 0xFFEF
// Stack Overflow/Underflow Reset Enable
// Stack Overflow or Underflow will cause a Reset
#define STVREN_ON 0xFFFF
// Stack Overflow or Underflow will not cause a Reset
#define STVREN_OFF 0xFDFF
// Brown-out Reset Voltage Selection
// Brown-out Reset Voltage (VBOR) set to 2.4V
#define BORV_LO 0xFFFF
// Brown-out Reset Voltage (VBOR) set to 2.7V
#define BORV_HI 0xFBFF
// Low-Power Brown Out Reset
// Low-Power BOR is disabled
#define LPBOR_OFF 0xFFFF
// Low-Power BOR is enabled
#define LPBOR_ON 0xF7FF
// Low-Voltage Programming Enable
// Low-voltage programming enabled
#define LVP_ON 0xFFFF
// High-voltage on MCLR/VPP must be used for programming
#define LVP_OFF 0xDFFF


//
// Special function register definitions
//


// Register: INDF0
volatile unsigned char INDF0 @ 0x000;
// bit and bitfield definitions

...
...
...

 

[Tahmid]

Can you post the complete .h file?

The portion you showed does not contain the UART definitions section.

 

[ragav4456]

Check the link

https://www.microchip.com/forums/tm.aspx?m=685603&high=

 

[ragav4456]

I solved UART communication.

I received data from microcontroller but datas are interchanged. Microcontroller sends different datas.

what is the problem?

 

[jayanth.devarayanadurga]

Are you getting garbage data? If yes, then your baudrate is not set properly or you have inverted the transmission or max232 is damaged.

 

[ragav4456]

this is my uart code.kindly check the code

#include <htc.h>
#include "sci.h"

unsigned int uiRS232Error = 0;

unsigned char sci_Init(unsigned long int baud, unsigned char ninebits)
{
	int X;
	unsigned long tmp;
	uiRS232Error = 0;

	tmp = 16UL * baud;
	X = (int)(FOSC/tmp) - 1;
	if((X>255) || (X<0))
	{
		tmp = 64UL * baud;
		X = (int)(FOSC/tmp) - 1;
		if((X>255) || (X<0))
		{
			return 1;	
		}
		else

			TX1STAbits.BRGH = 0;	/* low baud rate */
	}
	else
	TX1STAbits.BRGH = 1;	/* high baud rate */
	SPBRG = X;	/* set the baud rate */
        BAUD1CONbits.BRG16=1;
	BAUD1CONbits.ABDOVF=0;
	BAUD1CONbits.RCIDL=0;
	BAUD1CONbits.SCKP=0;
	BAUD1CONbits.WUE=0;
	BAUD1CONbits.ABDEN=1;
	TX1STAbits.SYNC = 0;           /* asynchronous */
	TX1STAbits.SENDB = 0;

	RC1STAbits.SPEN = 1;	/* enable serial port pins */
	RC1STAbits.CREN = 1;	/* enable reception */
	RC1STAbits.SREN = 0;	/* no effect */
	PIE1bits.TX1IE = 1;	/* disable tx interrupts */
	PIE1bits.RC1IE = 1;	/* disable rx interrupts */
	TX1STAbits.TX9  = ninebits?1:0;	/* 8- or 9-bit transmission */
	RC1STAbits.RX9  = ninebits?1:0;	/* 8- or 9-bit reception */
	RC2STAbits.ADDEN=0;
	TX1STAbits.TXEN = 1;	/* enable the transmitter */
	PIR1bits.TX1IF = 0;	/* enable tx interrupts */
	PIR1bits.RC1IF = 0; /* enable rx flag */

	return 0;
}

void sci_PutByte(unsigned char byte)
{	unsigned long ulICnt=0;
	
	uiRS232Error = 0;

	while(!PIR1bits.TX1IF && ulICnt < WAIT_TICK_MAX)	
	{	ulICnt++;
	}
	TX1REG = byte;

	if(ulICnt >= WAIT_TICK_MAX)
	{	uiRS232Error = 1;
	}
	return;
}

unsigned char sci_GetByte(void)
{	unsigned long ulICnt=0;

	uiRS232Error = 0;

	while(!PIR1bits.RC1IF && ulICnt < WAIT_TICK_MAX)	
	{	ulICnt++;
	}

	sci_CheckOERR();

	if(ulICnt >= WAIT_TICK_MAX)
	{	uiRS232Error = 1;
	}

	return RC1REG;	/* RXD9 and FERR are gone now */
}

unsigned char sci_CheckOERR(void)
{
	if(RC1STAbits.OERR)	
	{
		RC1STAbits.CREN = 0;
		RC1STAbits.CREN = 1;
		return 1;
	}
	
	return 0;
 }

#define sci_PutNinth(bitnine)	(TX9D = bitnine?1:0;)

unsigned char sci_GetNinth(void)
{
	while(!PIR1bits.RC1IF)
		continue;
	
	return RC1STAbits.RX9D;	
}

unsigned char sci_GetFERR(void)
{
	while(!PIR1bits.RC1IF)
		continue;
	
	return RC1STAbits.FERR;
}

 

[jayanth.devarayanadurga]

What is the purpose of the 2 nested if statements?

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tmp = 16UL * baud;
    X = (int)(FOSC/tmp) - 1;
    if((X>255) || (X<0))
    {
        tmp = 64UL * baud;
        X = (int)(FOSC/tmp) - 1;
        if((X>255) || (X<0))
        {
            return 1;   
        }
        else
 
            TX1STAbits.BRGH = 0;    /* low baud rate */
    }
    else
    TX1STAbits.BRGH = 1;    /* high baud rate */

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