Diff: main.cpp

Revision:

0:4be500de690c

Child:

1:bd9f39f9d91c

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Tue Mar 20 02:09:21 2018 +0000
@@ -0,0 +1,153 @@
+#include "mbed.h"
+#include "algorithm.h"
+#include "MAX30102.h"
+#include "LEDS.h"
+#include "WIFI.h"
+
+#define MAX_BRIGHTNESS 255
+extern int* ReadDS1621(void);
+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, TX-PA2, RX-PA3
+
+PwmOut pwmled(PA_10);  //initializes the pwm output PB3 that connects to the LED
+DigitalIn INT(PC_5);  //pin PB7 connects to the interrupt output pin of the MAX30102
+DigitalOut led(PC_9); //PC13 connects to the on board user LED
+AnalogIn xd(PA_0);
+AnalogIn yd(PA_1);
+AnalogIn zd(PA_4);
+
+// the setup routine runs once when you press reset:
+int main() { 
+    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;
+      int* temp;
+   
+    maxim_max30102_reset(); //resets the MAX30102
+    
+    // initialize serial communication at 115200 bits per second:
+    //pc.baud(115200);
+    //while(1);
+    //pc.format(8,SerialBase::None,1);
+    wait(5);
+    //init wifi
+    scan_demo(&wifi);
+    int ret = wifi.connect("Wo4G-YDL0", "by353006", NSAPI_SECURITY_WPA_WPA2);
+    if (ret != 0) {
+        pc.printf("\r\nConnection error\r\n");
+        return -1;
+    }
+
+    //wifi.disconnect();
+    //read and clear status register
+    maxim_max30102_read_reg(0,&uch_dummy);
+    
+    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
+        //pc.printf("red=%i", aun_red_buffer[i]);
+        //pc.printf(", ir=%i\n", aun_ir_buffer[i]);
+                wait(0.01);
+    }
+    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)
+    {
+        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)//just to determine the brightness of LED according to the deviation of adjacent two AD 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;
+            }
+
+            pwmled.write(1-(float)n_brightness/256);//pwm control led brightness
+                        if(n_brightness<120)
+                            led=1;
+                        else
+                            led=0;
+
+            //send samples and calculation result to terminal program through UART
+            //pc.printf("red=");
+            //pc.printf("%i", aun_red_buffer[i]);
+            //pc.printf(", ir=");
+            //pc.printf("%i", aun_ir_buffer[i]);
+                        temp = ReadDS1621();
+                        http_demo(&wifi);
+                        LightLEDs(n_heart_rate);
+            //pc.printf("HR=%i, temperature=%i:%i,SpO2=%i,x=%f,y=%f,z=%f\n", n_heart_rate,temp[0],temp[1],n_sp02,xd.read(),yd.read(),zd.read()); 
+                        //pc.printf("HR=%i\n", n_heart_rate); 
+            //pc.printf("HRvalid=%i, ", ch_hr_valid);
+            //pc.printf("SpO2=%i, ", n_sp02);
+            //pc.printf("SPO2Valid=%i\n\r", ch_spo2_valid);
+        }
+        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); 
+                wait(0.01);
+    }
+}