Diff: main.cpp

Revision:

0:4c7b37b8faad

Child:

1:1c14c1d3ce09

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Fri Jan 08 20:41:56 2016 +0000
@@ -0,0 +1,86 @@
+
+#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
+    }
+}