三线串口源码和头 (2).doc

/* ?2008 Microchip Technology Inc.* FileName: main.c* Dependencies: uart2.h* Processor: PIC24F* Compiler: MPLAB?C30* Tested On: PIC24F Explorer 16* SOFTWARE LICENSE AGREEMENT:* Microchip Technology Incorporated (Microchip) retains all ownership and * intellectual property rights in the code accompanying this message and in all * derivatives hereto. You may use this code, and any derivatives created by * any person or entity by or on your behalf, exclusively with Microchips* proprietary products. Your acceptance and/or use of this code constitutes * agreement to the terms and conditions of this notice.* CODE ACCOMPANYING THIS MESSAGE IS SUPPLIED BY MICROCHIP AS IS. NO * WARRANTIES, WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED * TO, IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A * PARTICULAR PURPOSE APPLY TO THIS CODE, ITS INTERACTION WITH MICROCHIPS * PRODUCTS, COMBINATION WITH ANY OTHER PRODUCTS, OR USE IN ANY APPLICATION. * YOU ACKNOWLEDGE AND AGREE THAT, IN NO EVENT, SHALL MICROCHIP BE LIABLE, WHETHER * IN CONTRACT, WARRANTY, TORT (INCLUDING NEGLIGENCE OR BREACH OF STATUTORY DUTY), * STRICT LIABILITY, INDEMNITY, CONTRIBUTION, OR OTHERWISE, FOR ANY INDIRECT, SPECIAL, * PUNITIVE, EXEMPLARY, INCIDENTAL OR CONSEQUENTIAL LOSS, DAMAGE, FOR COST OR EXPENSE OF * ANY KIND WHATSOEVER RELATED TO THE CODE, HOWSOEVER CAUSED, EVEN IF MICROCHIP HAS BEEN * ADVISED OF THE POSSIBILITY OR THE DAMAGES ARE FORESEEABLE. TO THE FULLEST EXTENT * ALLOWABLE BY LAW, MICROCHIPS TOTAL LIABILITY ON ALL CLAIMS IN ANY WAY RELATED TO * THIS CODE, SHALL NOT EXCEED THE PRICE YOU PAID DIRECTLY TO MICROCHIP SPECIFICALLY TO * HAVE THIS CODE DEVELOPED.* You agree that you are solely responsible for testing the code and * determining its suitability. Microchip has no obligation to modify, test, * certify, or support the code.* REVISION HISTORY:* Author Date Comments on this revision* Albert Z. 12/26/08 Original Release* ADDITIONAL NOTES: * Small, bare bones program to guide designers with UART implementation* To run the example, plug DB9 cable to Terminal (9600,8,N,1) - * Data sent from TERMINAL will be represented as binary equivalent* of ASCII on 7 LSB LEDs of Explorer 16 development board* Data is sent from Explorer 16 by pressing S3 - S6. A single letter will* be transmitted upon each keypress.* Peripheral Library was not utilized, Bit Addressing was used in order* to show all details involved in initialization of UART.* * This code example has been tested on Explorer 16 Development Board* with PIC24FJ128GA010, PIC24FJ256GA110 and PIC24FJ256GB110 PIMs. */#include p24fxxxx.h#include uart2.h#if defined (_PIC24FJ256GB110_)/Defined by MPLAB when using 24FJ256GB110 device _CONFIG1( JTAGEN_OFF & GCP_OFF & GWRP_OFF & COE_OFF & FWDTEN_OFF & ICS_PGx2) _CONFIG2( IESO_OFF & FCKSM_CSDCMD & OSCIOFNC_OFF & POSCMOD_XT & FNOSC_PRI & PLLDIV_DIV2 & IOL1WAY_ON) _CONFIG3( WPCFG_WPCFGDIS & WPDIS_WPDIS)/Disable erase/write protect of all memory regions.#elif defined (_PIC24FJ256GA110_)/Defined by MPLAB when using 24FJ256GA110 device _CONFIG1( JTAGEN_OFF & GCP_OFF & GWRP_OFF & COE_OFF & FWDTEN_OFF & ICS_PGx2 ) _CONFIG2( FCKSM_CSDCMD & OSCIOFNC_OFF & POSCMOD_XT & FNOSC_PRI & IOL1WAY_ON) _CONFIG3( WPCFG_WPCFGDIS & WPDIS_WPDIS)/Disable erase/write protect of all memory regions.#elif defined (_PIC24FJ128GA010_)/ JTAG/Code Protect/Write Protect/Clip-on Emulation mode/ Watchdog Timer/ICD pins select_CONFIG1(JTAGEN_OFF & GCP_OFF & GWRP_OFF & COE_OFF & FWDTEN_OFF & ICS_PGx2) / Disable CLK switch and CLK monitor, OSCO or Fosc/2, HS oscillator,/ Primary oscillator_CONFIG2(FCKSM_CSDCMD & OSCIOFNC_OFF & POSCMOD_XT & FNOSC_PRI)#endif#define TRUE1#define FALSE0unsigned char S3Flag, S4Flag, S5Flag, S6Flag;void _attribute_ (interrupt, no_auto_psv) _U2RXInterrupt(void) LATA = U2RXREG;IFS1bits.U2RXIF = 0;void _attribute_ (interrupt, no_auto_psv) _U2TXInterrupt(void) IFS1bits.U2TXIF = 0;void InitUART2(void) / This is an EXAMPLE, so brutal typing goes into explaining all bit sets/ The Explorer 16 board has a DB9 connector wired to UART2, so we will/ be configuring this port only/ configure U2MODEU2MODEbits.UARTEN = 0;/ Bit15 TX, RX DISABLED, ENABLE at end of funcU2MODEbits.USIDL = 0;/ Bit13 Continue in IdleU2MODEbits.IREN = 0;/ Bit12 No IR translationU2MODEbits.RTSMD = 0;/ Bit11 Simplex ModeU2MODEbits.UEN = 0;/ Bits8,9 TX,RX enabled, CTS,RTS notU2MODEbits.WAKE = 0;/ Bit7 No Wake up (since we dont sleep here)U2MODEbits.LPBACK = 0;/ Bit6 No Loop BackU2MODEbits.ABAUD = 0;/ Bit5 No Autobaud (would require sending 55)U2MODEbits.RXINV = 0;/ Bit4 IdleState = 1U2MODEbits.BRGH = 0;/ Bit3 16 clocks per bit periodU2MODEbits.PDSEL = 0;/ Bits1,2 8bit, No ParityU2MODEbits.STSEL = 0;/ Bit0 One Stop BitU2BRG = BAUDRATEREG2;/ baud rate/ Load all values in for U1STA SFRU2STAbits.UTXISEL1 = 0;/Bit15 Int when Char is transferred (1/2 config!)U2STAbits.UTXINV = 0;/Bit14 N/A, IRDA configU2STAbits.UTXISEL0 = 0;/Bit13 Other half of Bit15U2STAbits.UTXBRK = 0;/Bit11 DisabledU2STAbits.UTXEN = 0;/Bit10 TX pins controlled by periphU2STAbits.UTXBF = 0;/Bit9 *Read Only Bit*U2STAbits.TRMT = 0;/Bit8 *Read Only bit*U2STAbits.URXISEL = 0;/Bits6,7 Int. on character recievedU2STAbits.ADDEN = 0;/Bit5 Address Detect DisabledU2STAbits.RIDLE = 0;/Bit4 *Read Only Bit*U2STAbits.PERR = 0;/Bit3 *Read Only Bit*U2STAbits.FERR = 0;/Bit2 *Read Only Bit*U2STAbits.OERR = 0;/Bit1 *Read Only Bit*U2STAbits.URXDA = 0;/Bit0 *Read Only Bit*IFS1bits.U2TXIF = 0;/ Clear the Transmit Interrupt FlagIEC1bits.U2TXIE = 1;/ Enable Transmit InterruptsIFS1bits.U2RXIF = 0;/ Clear the Recieve Interrupt FlagIEC1bits.U2RXIE = 1;/ Enable Recieve InterruptsU2MODEbits.UARTEN = 1;/ And turn the peripheral onU2STAbits.UTXEN = 1;void InitPorts(void) / S3 (portD Pin 6, chosen as trigger for sending M to UART)/ S6 (portD Pin 7, chosen as trigger for sending C to UART)/ S5 (portA Pin 7, chosen as trigger for sending H to UART)/ S4 (portD Pin 13, chosen as trigger for sending P to UART)TRISD = 0x20C0;/ D6,7,13 inputsTRISA = 0x0080;/ only 0th bit needs be output. A7 is inputS3Flag = S4Flag = S5Flag = S6Flag = 0;/ Some Debounce Flagsvoid SoftwareDebounce(void) if(PORTDbits.RD6 = FALSE) if( S3Flag = FALSE ) S3Flag = TRUE; else if ( S3Flag = TRUE ) U2TXREG = M;S3Flag = FALSE;if(PORTDbits.RD7 = FALSE) if( S6Flag = FALSE ) S6Flag = TRUE; else if ( S6Flag = TRUE ) U2TXREG = C;S6Flag = FALSE;if(PORTAbits.RA7 = FALSE) if( S5Flag = FALSE ) S5Flag = TRUE; else if ( S5Flag = TRUE ) U2TXREG = H;S5Flag = FALSE;if(PORTDbits.RD13 = FALSE) if( S4Flag = FALSE ) S4Flag = TRUE; else if ( S4Flag = TRUE ) U2TXREG = P;S4Flag = FALSE;int main(void) unsigned char i;/ Disable Watch Dog TimerRCONbits.SWDTEN = 0;/ I/O remap, PPS#if defined (_PIC24FJ256GB110_) | defined (_PIC24FJ256GA110_)/ remap pins before intialising SPI2/ Unlock Registers_builtin_write_OSCCONL(OSCCON & 0xbf);/ Configure Input Functions */ Assign UART2RX To Pin RP10RPINR19bits.U2RXR = 10;/ Configure Output Functions */ Assign UART2TX To Pin RP17RPOR8bits.RP17R = U2TX_IO;/ Lock Registers_builtin_write_OSCCONL(OSCCON | 0x40);#endifInitUART2();/ Initialize UART2 for 9600,8,N,1 TX/RXInitPorts();/ LEDs outputs, Switches Inputswhile(1) / The ever versatile Infinite Loop!for (i = 0; i 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