Important changes to repositories hosted on mbed.com
Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.
To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.
It is also possible to export all your personal repositories from the account settings page.
Fork of BLEHeartRateMon by
Diff: source/main.cpp
- Revision:
- 47:8ae30057edc0
- Parent:
- 43:fb2855f7754b
- Child:
- 49:5be03f287022
diff -r 7d2e7f4a8e22 -r 8ae30057edc0 source/main.cpp
--- a/source/main.cpp Thu Nov 23 14:00:21 2017 +0000
+++ b/source/main.cpp Tue Dec 05 20:11:10 2017 +0000
@@ -19,13 +19,35 @@
#include "ble/BLE.h"
#include "ble/Gap.h"
#include "ble/services/HeartRateService.h"
+#include "algorithm.h"
+#include "MAX30102.h"
-DigitalOut led1(LED1, 1);
+#define MAX_BRIGHTNESS 255
+
+
+
+DigitalOut led2(LED2, 1);
+
+uint32_t aun_ir_buffer[500]; //IR LED sensor data
+int32_t n_ir_buffer_length; //data length
+uint32_t aun_red_buffer[500]; //Red LED sensor data
+int32_t n_sp02; //SPO2 value
+int8_t ch_spo2_valid; //indicator to show if the SP02 calculation is valid
+int32_t n_heart_rate; //heart rate value
+int8_t ch_hr_valid; //indicator to show if the heart rate calculation is valid
+uint8_t uch_dummy;
+
+Serial pc(USBTX, USBRX); //initializes the serial port
+#ifdef TARGET_MAX32630FTHR
+PwmOut led1(LED_RED); //initializes the pwm output that connects to the on board LED
+DigitalIn INT(P3_0); //pin P30 connects to the interrupt output pin of the MAX30102
+#endif
const static char DEVICE_NAME[] = "HRM";
static const uint16_t uuid16_list[] = {GattService::UUID_HEART_RATE_SERVICE};
static uint8_t hrmCounter = 100; // init HRM to 100bps
+//static uint8_t hrmCounter = n_heart_rate;
static HeartRateService *hrServicePtr;
static EventQueue eventQueue(/* event count */ 16 * EVENTS_EVENT_SIZE);
@@ -39,7 +61,7 @@
// Do blocking calls or whatever is necessary for sensor polling.
// In our case, we simply update the HRM measurement.
hrmCounter++;
-
+
// 100 <= HRM bps <=175
if (hrmCounter == 175) {
hrmCounter = 100;
@@ -50,7 +72,7 @@
void periodicCallback(void)
{
- led1 = !led1; /* Do blinky on LED1 while we're waiting for BLE events */
+ led2 = !led2; /* Do blinky on LED2 while we're waiting for BLE events */
if (BLE::Instance().getGapState().connected) {
eventQueue.call(updateSensorValue);
@@ -115,13 +137,123 @@
int main()
{
- eventQueue.call_every(500, periodicCallback);
+
+ //eventQueue.call_every(500, periodicCallback);
+
+ //BLE &ble = BLE::Instance();
+ //ble.onEventsToProcess(scheduleBleEventsProcessing);
+ //ble.init(bleInitComplete);
+
+ //eventQueue.dispatch_forever();
+
+ uint32_t un_min, un_max, un_prev_data; //variables to calculate the on-board LED brightness that reflects the heartbeats
+ int i;
+ int32_t n_brightness;
+ float f_temp;
+
+
+
+ maxim_max30102_reset(); //resets the MAX30102
- BLE &ble = BLE::Instance();
- ble.onEventsToProcess(scheduleBleEventsProcessing);
- ble.init(bleInitComplete);
+
+ //read and clear status register
+ maxim_max30102_read_reg(0,&uch_dummy);
+
+
+ //uch_dummy=getchar();
+
+ maxim_max30102_init(); //initializes the MAX30102
+
+ n_brightness=0;
+ un_min=0x3FFFF;
+ un_max=0;
+
+ n_ir_buffer_length=500; //buffer length of 100 stores 5 seconds of samples running at 100sps
+
+ //read the first 500 samples, and determine the signal range
+ for(i=0;i<n_ir_buffer_length;i++)
+ {
+ while(INT.read()==1); //wait until the interrupt pin asserts
+
+ maxim_max30102_read_fifo((aun_red_buffer+i), (aun_ir_buffer+i)); //read from MAX30102 FIFO
+
+ if(un_min>aun_red_buffer[i])
+ un_min=aun_red_buffer[i]; //update signal min
+ if(un_max<aun_red_buffer[i])
+ un_max=aun_red_buffer[i]; //update signal max
+
+ }
+ un_prev_data=aun_red_buffer[i];
+
+ //calculate heart rate and SpO2 after first 500 samples (first 5 seconds of samples)
+ maxim_heart_rate_and_oxygen_saturation(aun_ir_buffer, n_ir_buffer_length, aun_red_buffer, &n_sp02, &ch_spo2_valid, &n_heart_rate, &ch_hr_valid);
+
+
+
+ //Continuously taking samples from MAX30102. Heart rate and SpO2 are calculated every 1 second
+ while(1)
+ {
+
+ eventQueue.call_every(500, periodicCallback);
+
+ //BLE &ble = BLE::Instance();
+ //ble.onEventsToProcess(scheduleBleEventsProcessing);
+ //ble.init(bleInitComplete);
+
+ i=0;
+ un_min=0x3FFFF;
+ un_max=0;
+
+ //dumping the first 100 sets of samples in the memory and shift the last 400 sets of samples to the top
+ for(i=100;i<500;i++)
+ {
+ aun_red_buffer[i-100]=aun_red_buffer[i];
+ aun_ir_buffer[i-100]=aun_ir_buffer[i];
+
+ //update the signal min and max
+ if(un_min>aun_red_buffer[i])
+ un_min=aun_red_buffer[i];
+ if(un_max<aun_red_buffer[i])
+ un_max=aun_red_buffer[i];
+ }
+
+ //take 100 sets of samples before calculating the heart rate.
+ for(i=400;i<500;i++)
+ {
+ un_prev_data=aun_red_buffer[i-1];
+ while(INT.read()==1);
+ maxim_max30102_read_fifo((aun_red_buffer+i), (aun_ir_buffer+i));
+
+ if(aun_red_buffer[i]>un_prev_data)
+ {
+ f_temp=aun_red_buffer[i]-un_prev_data;
+ f_temp/=(un_max-un_min);
+ f_temp*=MAX_BRIGHTNESS;
+ n_brightness-=(int)f_temp;
+ if(n_brightness<0)
+ n_brightness=0;
+ }
+ else
+ {
+ f_temp=un_prev_data-aun_red_buffer[i];
+ f_temp/=(un_max-un_min);
+ f_temp*=MAX_BRIGHTNESS;
+ n_brightness+=(int)f_temp;
+ if(n_brightness>MAX_BRIGHTNESS)
+ n_brightness=MAX_BRIGHTNESS;
+ }
+#if defined(TARGET_KL25Z) || defined(TARGET_MAX32630FTHR)
+ led1.write(1-(float)n_brightness/256);
+#endif
- eventQueue.dispatch_forever();
- return 0;
+ }
+ maxim_heart_rate_and_oxygen_saturation(aun_ir_buffer, n_ir_buffer_length, aun_red_buffer, &n_sp02, &ch_spo2_valid, &n_heart_rate, &ch_hr_valid);
+
+ BLE &ble = BLE::Instance();
+ ble.onEventsToProcess(scheduleBleEventsProcessing);
+ ble.init(bleInitComplete);
+
+ eventQueue.dispatch_forever();
+ }
}
