main.cpp

00001 #include "mbed.h"
00002 #include "XBee.h"
00003 #include "TextLCD.h"
00004 
00005 TextLCD lcd(p25, p26, p24, p23, p22, p21); // RS, E, DB4, DB5, DB6, DB7
00006 
00007 /*-- AT command and parameters --*/
00008 uint8_t atISCmd[] = {'I', 'S'};      // Forces a read of all enabled digital and analog input lines
00009 uint8_t atDBCmd[] = {'D', 'B'};      // Received Signal Strength
00010 uint8_t cmdVal0[] = {0};             // Clear RSSI regisger
00011 
00012 /*-- Create instanse of Xbee object --*/
00013 XBee xbee(p13, p14);
00014 XBeeAddress64 remoteAddress(0x0013A200, 0x406B7111);    // Specify your XBee address
00015 
00016 /*-- Create instanse of Command and Response object --*/
00017 // Remot ATIS command to read ADC value (ADC3 is enabled by X-CTU tool)
00018 RemoteAtCommandRequest remoteSampleRequest(remoteAddress, atISCmd);
00019 // Local ATDB command to read signal strength (RSSI)
00020 AtCommandRequest atDB(atDBCmd);
00021 // Local ATDB0 command to clear RSSI
00022 AtCommandRequest atDB0(atDBCmd, cmdVal0, sizeof(cmdVal0));
00023 // Create instanse to handle command response
00024 AtCommandResponse response = AtCommandResponse();
00025 RemoteAtCommandResponse remoteResp = RemoteAtCommandResponse();
00026 
00027 
00028 /* Receive command response packet
00029  * If OK response recieved, return pointer to the Response Data Frame
00030  */
00031 uint8_t* GetResponse() {
00032     // Read response
00033     if (xbee.readPacket(5000)) {
00034         // Got a response! Check if response is AT command respose
00035         if (xbee.getResponse().getApiId() == AT_COMMAND_RESPONSE) {
00036             xbee.getResponse().getAtCommandResponse(response);
00037             if ( response.getStatus() == AT_OK ) 
00038                 return response.getValue();
00039         } else  if (xbee.getResponse().getApiId() == REMOTE_AT_COMMAND_RESPONSE) {
00040             xbee.getResponse().getRemoteAtCommandResponse(remoteResp);
00041             if ( remoteResp.getStatus() == AT_OK ) {
00042                // Debug print
00043                 printf("Response Data:");
00044                    for (int i = 0; i < remoteResp.getValueLength(); i++)
00045                    printf("%02X ", remoteResp.getValue()[i]);
00046                 printf("\n");
00047                 
00048                 return remoteResp.getValue();
00049             } else {
00050                 printf("Remote Command Error:0x%X\n", response.getStatus());
00051             }
00052         }
00053     }
00054 
00055     return 0;
00056 }
00057 
00058 
00059 /* Get ADC data
00060  * Data frame structure of ATIS
00061  * Offset
00062  *   0   : Number of Samples (Always 1)
00063  *   1-2 : Digital Channel Mask
00064  *   3   : Analog Channel Mask
00065  *   4-5 : Digital Samples (Omit if no DIO enabled)
00066  *   6-7 : First ADC Data
00067  */
00068 uint16_t getAnalog(uint8_t *FrameData, int ADC) {
00069     // ADC data feild starts 4 bytes offest, if no DIO enabled
00070     uint8_t start = 4;
00071 
00072     // Contains Digital channel?
00073     if (FrameData[1] > 0 || FrameData[2] > 0) {
00074         // make room for digital i/o
00075         start+=2;
00076     }
00077 
00078     // start depends on how many ADCs before this ADC are enabled
00079     for (int i = 0; i < ADC; i++) {
00080         // Is Analog channel Enabled ?
00081         if ( (FrameData[3] >> i) & 1 ) {
00082             start+=2;
00083         }
00084     }
00085 
00086     return (uint16_t)((FrameData[start] << 8) + FrameData[start + 1]);
00087 }
00088 
00089 
00090 int main() {
00091     unsigned int loop = 0;
00092 
00093     xbee.begin(9600);
00094     lcd.printf("RSSI:");
00095     lcd.locate(0, 1);
00096     lcd.printf("ADC :");
00097     printf("\nStart.\n");
00098 
00099     while (true) {
00100         uint8_t *responseVal;
00101         uint8_t rssiVal = 0;
00102         uint16_t adcVal = 0;
00103 
00104         // Send ATDB command (Read RSSI register from local Xbee)
00105         xbee.send(atDB);
00106         responseVal = GetResponse();
00107         if ( responseVal != 0 )
00108             rssiVal = responseVal[0];
00109         lcd.locate(5, 0);
00110         if (rssiVal == 0)
00111             lcd.printf("No Signal");
00112         else
00113             lcd.printf("-%ddBm   ", rssiVal);
00114 
00115         // Clear RSSI register, because Xbee hold RSSI value of last received packet even after radio disconneded
00116         xbee.send(atDB0);
00117         GetResponse();
00118 
00119         // Read ADC3 value by sending ATIS command
00120         xbee.send(remoteSampleRequest);
00121         responseVal = GetResponse();
00122         if ( responseVal != 0 ) {
00123             adcVal = getAnalog(responseVal, 3); // Assume ADC3 is enabled
00124         }
00125         lcd.locate(5, 1);
00126         if (adcVal == 0)
00127             lcd.printf("-     ");
00128         else
00129             lcd.printf("%d", adcVal);
00130     
00131         printf("Loop:%d\n", loop++);
00132         wait(1.0);
00133     }
00134 }