File content as of revision 0:4c7b37b8faad:

#include "mbed.h"
#include "BLEDevice.h"
#include "ADXL345.h"

// The accelerometer sample rate defines how often advertising
// packets need to be sent. Each packet can hold 9 samples.
#define ACC_SAMPLE_RATE     9

// How many times to re-advertise the same packet. For example,
// if for the given sample rate an advertising packet needs to
// be sent every second, and ADV_RESEND_COUNT of 2 will send
// 2 packets per second.
#define ADV_RESEND_COUNT    10

BLEDevice   ble;
ADXL345     acc(P0_9, P0_11, P0_8, P0_10);
DigitalOut  led(P0_19);

void accRead() {
    int data[3];
    static int8_t buffer[28];
    static uint8_t index = 0;
    static uint8_t count;
    
    acc.getOutput(data);
    
    // Fill buffer
    buffer[index] = (int8_t)(data[0] >> 8);
    buffer[index+1] = (int8_t)(data[1] >> 8);
    buffer[index+2] = (int8_t)(data[2] >> 8);
    index += 3;
    
    // If buffer is full (9 readings) update advertising packet
    if (index >= 27) {
        index = 0;                      // Reset buffer index
        count += 1;                     // Increase packet count
        buffer[27] = count;             // Append packet count
        ble.clearScanResponse();        // Clear advertising packet and add data
        ble.accumulateScanResponse(GapAdvertisingData::MANUFACTURER_SPECIFIC_DATA, (uint8_t*)buffer, sizeof(buffer));
        ble.setAdvertisingPayload();
        led = 0;                        // Flash led
        wait(0.01);
        led = 1;
    }
}
    
    
int main(void) {
    // Turn off led
    led = 0;
    
    // Calculate advertising interval
    uint16_t adv_interval;
    adv_interval = (uint16_t)((9.0 / (float)ACC_SAMPLE_RATE) * 1000.0 / (float)ADV_RESEND_COUNT);
    
    // Initialize BLE
    uint8_t tagAddress[6];
    uint8_t tagName[8];
    ble.init();                                             // Initialize BLE stack
    ble.setTxPower(4);                                      // Set power level (in dB)
    ble.setAddress(Gap::ADDR_TYPE_RANDOM_STATIC, NULL);     // Static random address
    ble.getAddress(NULL, tagAddress);                       // Get random address from stack
    sprintf((char*)tagName, "TAG_%2X%2X", tagAddress[1], tagAddress[0]);
    ble.accumulateAdvertisingPayload(                       // Advertise as BLE
        GapAdvertisingData::BREDR_NOT_SUPPORTED |
        GapAdvertisingData::LE_GENERAL_DISCOVERABLE);
    ble.accumulateAdvertisingPayload(                       // Set name
        GapAdvertisingData::COMPLETE_LOCAL_NAME,
        tagName,
        sizeof(tagName));
    ble.setAdvertisingInterval(adv_interval);               // Advertising interval
    ble.startAdvertising();                                 // Start advertising
    
    // Setup ticker to read accelerometer
    acc.setPowerControl(0x00);      // Standby for configuration
    acc.setDataFormatControl(0x05); // +-4g, left-justified,
    acc.setDataRate(ADXL345_12HZ5); // 12.5Hz Internal Sample Rate
    acc.setPowerControl(0x08);      // Measurement mode
    Ticker acc_read;
    acc_read.attach(&accRead, (1.0 / (float)ACC_SAMPLE_RATE));
    
    while(1) {
        ble.waitForEvent();     // Sleep
    }
}