Subversion Repositories Code-Repo

#include "defines.h"

#include "xbee.h"

#include <string.h>

#pragma udata XBEE_BUFFER

static XBEE_DATA xbee_data;

#pragma udata

static XBEE_DATA *xbee_data_p = &xbee_data;

static void *xbee_data_frame;

static void *xbee_frame;

/* Initialize variables used by this library */

void XBee_Init() {

    XBEE_CTS_TRIS = 1; // RB0 is CTS, set by XBee chip

    XBEE_RTS_TRIS = 0; // RB1 is RTS, set by PIC

    XBEE_CTS_LAT = 0; // Pin set high to signal stop sending data to XBee

    XBEE_RTS_LAT = 0; // Pin set high to indicate stop sending data to PIC

    xbee_data_p->dataind = 0;

    xbee_data_p->checksum_sum = 0;

    xbee_data_p->frame_rdy = 0;

    xbee_data_p->escape_flag = 0;

    xbee_data_p->read_state = XBEE_STATE_READ_START;

//    memset(&xbee_data, 0, 32);

    // Grab a pointer to where the unique frame array starts

    xbee_data_frame = &(xbee_data_p->rcv_frame.FRAME);

    xbee_frame = &(xbee_data_p->rcv_frame);

}

/* Here we handle the serial input from the UART interrupt */

void XBee_Serial_In(unsigned char c) {

    // For some reason writing the length straight to xbee_data doesnt seem to work

    //  so we work around it by pointing to the length bytes directly

    XBEE_ADDRESS_16 *length = xbee_frame + 1;

#ifdef XBEE_USE_ESCAPE_CHAR

    if (c == XBEE_ESCAPE_CHAR) {

        // Next byte needs is an escaped char

        xbee_data_p->escape_flag = 1;

        return;

    }

    if (xbee_data_p->escape_flag) {

        // XOR byte with 0x20 to get escaped char

        c ^= XBEE_ESCAPE_VAL;

        xbee_data_p->escape_flag = 0;

    }

#endif

    // Reset on start bit and start saving data

    if (c == XBEE_START_DELIMITER) {

        // On detect start delimiter, clear out initial array

        xbee_data_p->dataind = 0;

        xbee_data_p->checksum_sum = 0;

        xbee_data_p->frame_rdy = 0;

        xbee_data_p->read_state = XBEE_STATE_READ_LENGTH_HIGH;

        *((unsigned char *)xbee_frame) = XBEE_START_DELIMITER;

    } else {

        switch (xbee_data_p->read_state) {

            case XBEE_STATE_READ_START:

                // Do nothing and wait till start bit is read

                break;

            case XBEE_STATE_READ_LENGTH_HIGH:

                // Read length (MSB)

                length->INT_16.char_value[1] = c;

                xbee_data_p->read_state = XBEE_STATE_READ_LENGTH_LOW;

                break;

            case XBEE_STATE_READ_LENGTH_LOW:

                // Read length (LSB)

                length->INT_16.char_value[0] = c;

                xbee_data_p->read_state = XBEE_STATE_READ_FRAME_DATA;

                break;

            case XBEE_STATE_READ_FRAME_DATA:

                // Read unique frame data

                if (xbee_data_p->dataind < xbee_data_p->rcv_frame.length.INT_16.int_value) {

                    *((char*) xbee_data_frame + xbee_data_p->dataind) = c;

                    xbee_data_p->checksum_sum += c;

                    xbee_data_p->dataind++;

                }

                // If total length is read, the next byte is the expected checksum

                if (xbee_data_p->dataind == xbee_data_p->rcv_frame.length.INT_16.int_value) {

                    xbee_data_p->read_state = XBEE_STATE_READ_CHECKSUM;

                }

                break;

            case XBEE_STATE_READ_CHECKSUM:

                // Calculate and compare checksum

                if (0xFF - xbee_data_p->checksum_sum == c) {

                    // Frame was recieved successfully

                    xbee_data_p->frame_rdy = 1;

//                    XBee_Process_Received_Frame();

                } else {

                    // If checksum does not match, drop frame

                    DBG_PRINT_XBEE("XBEE: checksum mismatch\r\n");

                }

                xbee_data_p->read_state = XBEE_STATE_READ_START;

                break;

        }

    }

}

/* This processes the frame data within the interrupt. Dont use this. */

void XBee_Process_Received_Frame() {

//    DBG_PRINT_XBEE("Length: %d\r\n", xbee_data_p->rcv_frame.length.INT_16.int_value);

    // Here we process the received frame depending on the frame type

    switch (*((unsigned char *) xbee_data_frame)) {

        case XBEE_RX_AT_COMMAND_RESPONSE:

            DBG_PRINT_XBEE("XBEE: parsing recieved AT command response frame\r\n");

            break;

        case XBEE_RX_DATA_PACKET:

            DBG_PRINT_XBEE("XBEE: parsing recieved data frame\r\n");

            break;

        case XBEE_RX_DATA_TX_STATUS:

            DBG_PRINT_XBEE("XBEE: parsing recieved TX status frame\r\n");

            break;

        case XBEE_RX_IO_DATA_SAMPLE:

            DBG_PRINT_XBEE("XBEE: parsing recieved IO data sample frame\r\n");

            break;

        case XBEE_RX_EXPLICIT_COMMAND:

            DBG_PRINT_XBEE("XBEE: parsing recieved explicit command frame\r\n");

            break;

        case XBEE_RX_REMOTE_AT_COMMAND_RESPONSE:

            DBG_PRINT_XBEE("XBEE: parsing recieved remote AT command frame\r\n");

            break;

        case XBEE_RX_ROUTE_RECORD:

            DBG_PRINT_XBEE("XBEE: parsing recieved route record frame\r\n");

            break;

        case XBEE_RX_NODE_IDENTIFICATION:

            DBG_PRINT_XBEE("XBEE: parsing recieved node identification frame\r\n");

            break;

        case XBEE_RX_FRAME_MODEM_STATUS:

            DBG_PRINT_XBEE("XBEE: parsing recieved modem status frame\r\n");

            break;

        default:

            DBG_PRINT_XBEE("XBEE: (ERROR) unrecognized frame type\r\n");

    }

}

unsigned int XBee_Get_Received_Frame(unsigned char *frame) {

    if (!xbee_data_p->frame_rdy) {

        return 0;

    } else {

        memcpy(frame, xbee_data_frame, xbee_data_p->rcv_frame.length.INT_16.int_value);

        xbee_data_p->frame_rdy = 0; // Reset frame ready status

        return xbee_data_p->rcv_frame.length.INT_16.int_value;

    }

}

void XBee_Process_Transmit_Frame(unsigned char *data, unsigned char length) {

#ifdef XBEE_USE_ESCAPE_CHAR

    unsigned int i = 0;

    unsigned char chksum = 0;

    // Write the start bit and length

    UART1_WriteC(XBEE_START_DELIMITER);

    UART1_WriteC(0);

    UART1_WriteC(length);

    // Write the frame data

    for (i = 0; i < length; i++) {

        chksum += data[i];

        if (data[i] == XBEE_START_DELIMITER ||     \

                data[i] == XBEE_ESCAPE_CHAR ||     \

                data[i] == XBEE_XON ||     \

                data[i] == XBEE_XOFF) {

            UART1_WriteC(XBEE_ESCAPE_CHAR);

            UART1_WriteC(data[i] ^ XBEE_ESCAPE_VAL);

        } else {

            UART1_WriteC(data[i]);

        }

    }

    // Write the checksum

    if (chksum == XBEE_START_DELIMITER ||     \

                chksum == XBEE_ESCAPE_CHAR ||     \

                chksum == XBEE_XON ||     \

                chksum == XBEE_XOFF) {

        UART1_WriteC(XBEE_ESCAPE_CHAR);

        UART1_WriteC(chksum ^ XBEE_ESCAPE_VAL);

    } else {

        UART1_WriteC(0xFF - chksum);

    }

#else

    unsigned int i = 0;

    unsigned char chksum = 0;

    UART1_WriteC(XBEE_START_DELIMITER);

    UART1_WriteC(0);

    UART1_WriteC(length);

    for (i = 0; i < length; i++) {

        chksum += data[i];

        UART1_WriteC(data[i]);

    }

    UART1_WriteC(0xFF - chksum);

#endif

}

void XBee_Set_RTS(unsigned char c) {

    if (c) {

        XBEE_RTS_LAT = 1; // Set high to stop receiving data

    } else {

        XBEE_RTS_LAT = 0; // Set low to resume receiving data

    }

}

unsigned char XBee_Read_CTS() {

    unsigned char c = XBEE_CTS_PORT;

    if (c) {

        return 0x1; // High indicates stop sending data

    } else {

        return 0x0; // Low indicates ok to send data

    }

}

void XBee_Convert_Endian_64(XBEE_ADDRESS_64 *src) {

    char tmp[2];

    tmp[0] = src->UPPER_32.char_value[3];

    tmp[1] = src->UPPER_32.char_value[2];

    src->UPPER_32.char_value[3] = src->UPPER_32.char_value[0];

    src->UPPER_32.char_value[2] = src->UPPER_32.char_value[1];

    src->UPPER_32.char_value[1] = tmp[1];

    src->UPPER_32.char_value[0] = tmp[0];

    tmp[0] = src->LOWER_32.char_value[3];

    tmp[1] = src->LOWER_32.char_value[2];

    src->LOWER_32.char_value[3] = src->LOWER_32.char_value[0];

    src->LOWER_32.char_value[2] = src->LOWER_32.char_value[1];

    src->LOWER_32.char_value[1] = tmp[1];

    src->LOWER_32.char_value[0] = tmp[0];

}

void XBee_Convert_Endian_16(XBEE_ADDRESS_16 *src) {

    char tmp;

    tmp = src->INT_16.char_value[0];

    src->INT_16.char_value[0] = src->INT_16.char_value[1];

    src->INT_16.char_value[1] = tmp;

}