Introduction
The XBee, RS-232 and USB versions of the XRW2G module can be set to World Data Mode by placing a jumper on the internal JP3 header. The jumper must be in place on start-up. In this mode, the XRW2G will transmit a 98 byte data packet over the serial port at user defined intervals. The XBee version transmits the packet using a 2.4GHz 802.15.4 XBee-PRO wireless transceiver. Channel D is used with the default PAN ID. You will need an XBee-PRO or XBee modem to receive data for your application. We manufacture a variety of XBee and XBee-PRO modems.
Data Format
'#' 0 STX UNIT ID PREFIX 1 First character (A-Z) for serial number UNIT ID MSB 2 high byte of sending station ID UNIT ID LSB 3 low byte of sending station ID PACKET LENGTH 4 number of byte for packet including STX through CRC PACKET TYPE 5 type of packet we are sending, 14 SEQUENCE MSB 6 SEQUENCE LSB 7 PULSE_COUNT[0] MSB 8 PULSE_COUNT[0] LSB 9 PULSE_TIME[0] MSB 10 PULSE_TIME[0] LSB 11 PULSE_MIN_TIME[0] MSB 12 PULSE_MIN_TIME[0] LSB 13 PULSE_MAX_TIME[0] MSB 14 PULSE_MAX_TIME[0] LSB 15 PULSE_SUM[0] MSB 16 PULSE_SUM[0] 17 PULSE_SUM[0] 18 PULSE_SUM[0] LSB 19 PULSE_COUNT[1] MSB 20 PULSE_COUNT[1] LSB 21 PULSE_TIME[1] MSB 22 PULSE_TIME[1] LSB 23 PULSE_MIN_TIME[1] MSB 24 PULSE_MIN_TIME[1] LSB 25 PULSE_MAX_TIME[1] MSB 26 PULSE_MAX_TIME[1] LSB 27 PULSE_SUM[1] MSB 28 PULSE_SUM[1] 29 PULSE_SUM[1] 30 PULSE_SUM[1] LSB 31 PULSE_COUNT[2] MSB 32 PULSE_COUNT[2] LSB 33 PULSE_TIME[2] MSB 34 PULSE_TIME[2] LSB 35 PULSE_MIN_TIME[2] MSB 36 PULSE_MIN_TIME[2] LSB 37 PULSE_MAX_TIME[2] MSB 38 PULSE_MAX_TIME[2] MSB 39 PULSE_SUM[2] MSB 40 PULSE_SUM[2] 41 PULSE_SUM[2] 42 PULSE_SUM[2] LSB 43 ANALOG_CURRENT[0] MSB 44 ANALOG_CURRENT[0] LSB 45 ANALOG_AVG[0] MSB 46 ANALOG_AVG[0] LSB 47 ANALOG_STD_DEV[0] MSB 48 ANALOG_STD_DEV[0] LSB 49 ANALOG_CURRENT[1] MSB 50 ANALOG_CURRENT[1] LSB 51 ANALOG_AVG[1] MSB 52 ANALOG_AVG[1] LSB 53 ANALOG_STD_DEV[1] MSB 54 ANALOG_STD_DEV[1] LSB 55 ANALOG_CURRENT[2] MSB 56 ANALOG_CURRENT[2] LSB 57 ANALOG_AVG[2] MSB 58 ANALOG_AVG[2] LSB 59 ANALOG_STD_DEV[2] MSB 60 ANALOG_STD_DEV[2] LSB 61 ANALOG_CURRENT[3] MSB 62 ANALOG_CURRENT[3] LSB 63 ANALOG_AVG[3] MSB 64 ANALOG_AVG[3] LSB 65 ANALOG_STD_DEV[3] MSB 66 ANALOG_STD_DEV[3] LSB 67 ANALOG_CURRENT[4] MSB 68 ANALOG_CURRENT[4] LSB 69 ANALOG_AVG[4] MSB 70 ANALOG_AVG[4] LSB 71 ANALOG_STD_DEV[4] MSB 72 ANALOG_STD_DEV[4] LSB 73 ANALOG_CURRENT[5] MSB 74 ANALOG_CURRENT[5] LSB 75 ANALOG_AVG[5] MSB 76 ANALOG_AVG[5] LSB 77 ANALOG_STD_DEV[5] MSB 78 ANALOG_STD_DEV[5] LSB 79 ANALOG_CURRENT[6] MSB 80 ANALOG_CURRENT[6] LSB 81 ANALOG_AVG[6] MSB 82 ANALOG_AVG[6] LSB 83 ANALOG_STD_DEV[6] MSB 84 ANALOG_STD_DEV[6] LSB 85 ANALOG_CURRENT[7] MSB 86 ANALOG_CURRENT[7] LSB 87 ANALOG_AVG[7] MSB 88 ANALOG_AVG[7] LSB 89 ANALOG_STD_DEV[7] MSB 90 ANALOG_STD_DEV[7] LSB 91 UPTIME_MINUTES MSB 92 UPTIME_MINUTES LSB 93 INTERVAL MS MSB 94 INTERVAL MS LSB 95 CRC MSB 96 high byte of CRC on everything after STX and before CRC CRC LSB 97 low byte of CRC
Example Code:
C CRC Function
int16 crc_chk(int8 *data, int8 length) {
int8 j;
int16 reg_crc=0xFFFF;
while ( length-- ) {
reg_crc ^= *data++;
for ( j=0 ; j<8 ; j++ ) {
if ( reg_crc & 0x01 ) {
reg_crc=(reg_crc>>1) ^ 0xA001;
} else {
reg_crc=reg_crc>>1;
}
}
}
return reg_crc;
}