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#include <pic18.h>
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#include "barcode.h"
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/*************************
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globals
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************************/
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char global_barcode_buffer[14];
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/***********************
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module vars
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*************************/
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unsigned char barcode_length;
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bit barcode_ready;
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/*************************
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function
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*************************/
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void barcode_init(void)
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{
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SPEN = 0; //Make sure serial port is disabled
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// snupset fra Kim H Pedersens serialmain.c
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// Set Port C bit 6 output (TxD) and bit 7 input (RxD)
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TRISC6 = 0;
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TRISC7 = 1;
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/*
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SPBRG = 25; // x = Fosc/(16 * Baud Rate) - 1
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// x = 4000000/(16 * 9600) - 1
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// x = 25.0417 ~ 25
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// Baud Rate = Fosc/(16 * (x+1))
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// Baud Rate = 4000000/(16 * (25+1))
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// Baud Rate = 9615
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*/
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SPBRG = 130; //BRG værdi for 20Mhz MCU
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TXSTA = 0x24; // TXSTA7 = 0 Don't care in asynchronous
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// TXSTA6 = 0 8-bit transmission
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// TXSTA5 = 1 Transmit enabled
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// TXSTA4 = 0 Asynchronous mode
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// TXSTA3 = 0 Unimplemented
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// TXSTA2 = 1 High speed
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// TXSTA1 = 0 TSR empty
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// TXSTA0 = 0 9th bit
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RCSTA = 0x90; // RCSTA7 = 0 Serial port disabled
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// RCSTA6 = 0 8-bit reception
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// RCSTA5 = 0 Don't care in asynchronous
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// RCSTA4 = 1 Receiver enabled
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// RCSTA3 = 0 Don't care (8-bit operation)
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// RCSTA2 = 0 No framing error
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// RCSTA1 = 0 Overrun error bit
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// RCSTA0 = 0 9th bit
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//config completed
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SPEN = 1; //Enable Serial port
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//Set module-scope variables
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barcode_length = 0;
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barcode_ready = 0;
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//Configure interrupts
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TXIE = 0; //Disable AUX TX interrupt - testes med TXIF;
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RCIE = 1; //Enable AUX Recieve interrupt - testes med RCIF;
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IPEN = 0; // IPEN=Interrupt Priority ENable bit - her bruges ingen prioritet
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PEIE = 1; // PEIE = PEriphal Interrupt Enable
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TXIF = 0; //nulstil intterupt flag
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RCIF = 0;
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GIE = 1; //Global interrupt enable bit
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}
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void barcode_reset(void)
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{
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barcode_length = 0;
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barcode_ready = 0;
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}
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unsigned char barcode_is_ready(void)
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{
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return barcode_ready;
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}
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unsigned char barcode_get_length()
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{
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return barcode_length;
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}
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/* interrupt entry function - barcode is the only module using interrupts */
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void /*interrupt*/ barcode_interrupt(void)
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{
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char data = RCREG;
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RCIF = 0;
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if (barcode_ready == 0)
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{
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if (data == '\r')
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{
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return;
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}
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else if (data == '\n')
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{
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barcode_ready = 1;
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}
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else
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{
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global_barcode_buffer[barcode_length++] = RCREG;
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}
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}
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}
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