truyền nhận bằng UART trong PIC24

[quangdk]

không biết các bạn đã làm chưa, đã lâu mình khong vào diễn đàn, mình post thử code của mình về truyền nhận UART. K biết có lạc hậu quá không!Mong các bạn góp ý

/************************************************** ***************************
*
* UART Driver for PIC24.
*
************************************************** ***************************
* FileName: uart2.c
* Dependencies: system.h
* Processor: PIC24
* Compiler: MPLAB C30
* Linker: MPLAB LINK30
* Company: Microchip Technology Incorporated
*
* Software License Agreement
*
* The software supplied herewith by Microchip Technology Incorporated
* (the "Company") is intended and supplied to you, the Company's
* customer, for use solely and exclusively with products manufactured
* by the Company.
*
* The software is owned by the Company and/or its supplier, and is
* protected under applicable copyright laws. All rights are reserved.
* Any use in violation of the foregoing restrictions may subject the
* user to criminal sanctions under applicable laws, as well as to
* civil liability for the breach of the terms and conditions of this
* license.
*
* THIS SOFTWARE IS PROVIDED IN AN "AS IS" CONDITION. NO WARRANTIES,
* WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED
* TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE COMPANY SHALL NOT,
* IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR
* CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
*
* A simple UART polled driver
*
* Author Date Comment
*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~
* Anton Alkhimenok 10/18/05 ...
* Brant Ivey 3/14/06 Added support for PIC24FJ64004 PIM
************************************************** ***************************/
#include "system.h"

/************************************************** ***************************
* U2BRG register value and baudrate mistake calculation
************************************************** ***************************/
#define BAUDRATEREG2 SYSCLK/32/BAUDRATE2-1

#if BAUDRATEREG2 > 255
#error Cannot set up UART2 for the SYSCLK and BAUDRATE.\
Correct values in main.h and uart2.h files.
#endif

#define BAUDRATE_MISTAKE 1000*(BAUDRATE2-SYSCLK/32/(BAUDRATEREG2+1))/BAUDRATE2
#if (BAUDRATE_MISTAKE > 2)||(BAUDRATE_MISTAKE < -2)
#error UART2 baudrate mistake is too big for the SYSCLK\
and BAUDRATE2. Correct values in uart2.c file.
#endif

/************************************************** ***************************
* Function: UART2Init
*
* Precondition: None.
*
* Overview: Setup UART2 module.
*
* Input: None.
*
* Output: None.
*
************************************************** ***************************/
void UART2Init()
{
// Set directions of UART IOs
UART2_TX_TRIS = 0;
UART2_RX_TRIS = 1;
U2BRG = BAUDRATEREG2;
U2MODE = 0;
U2STA = 0;
U2MODEbits.UARTEN = 1;
U2STAbits.UTXEN = 1;
// reset RX flag
IFS1bits.U2RXIF = 0;
}

/************************************************** ***************************
* Function: UART2PutChar
*
* Precondition: UART2Init must be called before.
*
* Overview: Wait for free UART transmission buffer and send a byte.
*
* Input: Byte to be sent.
*
* Output: None.
*
************************************************** ***************************/
void UART2PutChar(char Ch){
// wait for empty buffer
while(U2STAbits.UTXBF == 1);
U2TXREG = Ch;
}

/************************************************** ***************************
* Function: UART2IsPressed
*
* Precondition: UART2Init must be called before.
*
* Overview: Check if there's a new byte in UART reception buffer.
*
* Input: None.
*
* Output: Zero if there's no new data received.
*
************************************************** ***************************/
char UART2IsPressed()
{
if(IFS1bits.U2RXIF == 1)
return 1;
return 0;
}

/************************************************** ***************************
* Function: UART2GetChar
*
* Precondition: UART2Init must be called before.
*
* Overview: Wait for a byte.
*
* Input: None.
*
* Output: Byte received.
*
************************************************** ***************************/
char UART2GetChar(){
char Temp;
while(IFS1bits.U2RXIF == 0);
Temp = U2RXREG;
IFS1bits.U2RXIF = 0;
return Temp;
}

/************************************************** ***************************
* Function: UART2PutDec
*
* Precondition: UART2Init must be called before.
*
* Overview: This function converts decimal data into a string
* and outputs it into UART.
*
* Input: Binary data.
*
* Output: None.
*
************************************************** ***************************/
void UART2PutDec(unsigned char Dec){
unsigned char Res;
Res = Dec;

if(Res/100)
UART2PutChar(Res/100+'0');
Res = Res - (Res/100)*100;

if(Res/10)
UART2PutChar(Res/10+'0');
Res = Res - (Res/10)*10;

UART2PutChar(Res+'0');
}

/************************************************** ***************************

/************************************************** ***************************
*
* UART Driver for PIC24.
* Modified for PIC24FJ64GA004 family with PPS.
*
************************************************** ***************************
* FileName: uart2.c
* Dependencies: system.h
* Processor: PIC24
* Compiler: MPLAB C30
* Linker: MPLAB LINK30
* Company: Microchip Technology Incorporated
*
* Software License Agreement
*
* The software supplied herewith by Microchip Technology Incorporated
* (the "Company") is intended and supplied to you, the Company's
* customer, for use solely and exclusively with products manufactured
* by the Company.
*
* The software is owned by the Company and/or its supplier, and is
* protected under applicable copyright laws. All rights are reserved.
* Any use in violation of the foregoing restrictions may subject the
* user to criminal sanctions under applicable laws, as well as to
* civil liability for the breach of the terms and conditions of this
* license.
*
* THIS SOFTWARE IS PROVIDED IN AN "AS IS" CONDITION. NO WARRANTIES,
* WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED
* TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE COMPANY SHALL NOT,
* IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR
* CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
*
* A simple UART polled driver
*
* Author Date Comment
*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~
* Anton Alkhimenok 10/18/05 ...
* Brant Ivey 3/14/06 Modified for PIC24FJ64GA004 family with PPS.
************************************************** ***************************/

#include "iomapping.h"

/************************************************** ***************************
* DEFINITIONS
************************************************** ***************************/
// Baudrate
#define BAUDRATE2 19200

// UART IOs
#ifdef PPS_UART2_TX_TRIS
#define UART2_TX_TRIS PPS_UART2_TX_TRIS
#define UART2_RX_TRIS PPS_UART2_RX_TRIS
#else
#define UART2_TX_TRIS TRISFbits.TRISF12
#define UART2_RX_TRIS TRISFbits.TRISF13
#endif


/************************************************** ***************************
* Function: UART2Init
*
* Precondition: None.
*
* Overview: Setup UART2 module.
*
* Input: None.
*
* Output: None.
*
************************************************** ***************************/
extern void UART2Init();

/************************************************** ***************************
* Function: UART2PutChar
*
* Precondition: UART2Init must be called before.
*
* Overview: Wait for free UART transmission buffer and send a byte.
*
* Input: Byte to be sent.
*
* Output: None.
*
************************************************** ***************************/
extern void UART2PutChar(char Ch);

/************************************************** ***************************
* Function: UART2IsPressed
*
* Precondition: UART2Init must be called before.
*
* Overview: Check if there's a new byte in UART reception buffer.
*
* Input: None.
*
* Output: Zero if there's no new data received.
*
************************************************** ***************************/
extern char UART2IsPressed();

/************************************************** ***************************
* Function: UART2GetChar
*
* Precondition: UART2Init must be called before.
*
* Overview: Wait for a byte.
*
* Input: None.
*
* Output: Byte received.
*
************************************************** ***************************/
extern char UART2GetChar();

/************************************************** ***************************
* Function: UART2PutDec
*
* Precondition: UART2Init must be called before.
*
* Overview: This function converts decimal data into a string
* and outputs it into UART.
*
* Input: Binary data.
*
* Output: None.
*
************************************************** ***************************/
extern void UART2PutDec(unsigned char Dec);

/************************************************** ***************************
* EOF
************************************************** ***************************/

#include "system.h"
//#include "LCD.h"

_CONFIG1(JTAGEN_OFF & GCP_OFF & GWRP_OFF & BKBUG_ON & ICS_PGx2 & FWDTEN_OFF)
_CONFIG2(IESO_OFF & FCKSM_CSDCMD & OSCIOFNC_ON & FNOSC_PRI & POSCMOD_HS)


// useful macros for VT100 terminal emulation
#define clrscr() UART2PutChar( "\x1b[2J")
#define home() UART2PutChar( "\x1b[1,1H")

#define COL 40
#define ROW 23

//#define DELAY 1000

main()
{
char c;
//initLCD(); // initializations
UART2Init();
UART2PutChar('s');

while (1)
{
c=UART2GetChar();
UART2PutChar(c);
//UART2PutChar( "Learn to fly with the PIC24!");
//UART2PutChar('\n');
}
}