Buenas grupo,
estoy tratando de hacer que las lecturas de ritmo cardiaco y de spo2 tomadas mediante el sensor MAX30102 se muestren por mi OLED. Sin embargo, esto nunca ocurre.
He ido probando a depurar el código escribiendo mensajes en la OLED en distintos lugares del código, y siempre me lo imprime salvo cuando entro el el while(1) que se encarga de imprimir por serial los valores tomados del sensor, concretamente en esta parte del código:
while (1)
{
if(x==0){
escribir_texto(0,0,"Hasta aquí llego",1);
}
//dumping the first 25 sets of samples in the memory and shift the last 75 sets of samples to the top
for (byte i = 25; i < 100; i++)
{
redBuffer[i - 25] = redBuffer[i];
irBuffer[i - 25] = irBuffer[i];
}
//take 25 sets of samples before calculating the heart rate.
for (byte i = 75; i < 100; i++)
{
while (particleSensor.available() == false) //do we have new data?
particleSensor.check(); //Check the sensor for new data
digitalWrite(readLED, !digitalRead(readLED)); //Blink onboard LED with every data read
redBuffer[i] = particleSensor.getRed();
irBuffer[i] = particleSensor.getIR();
particleSensor.nextSample(); //We're finished with this sample so move to next sample
//send samples and calculation result to terminal program through UART
Serial.print(F("red="));
Serial.print(redBuffer[i], DEC);
Serial.print(F(", ir="));
Serial.print(irBuffer[i], DEC);
Serial.print(F(", HR="));
Serial.print(heartRate, DEC);
escribir_texto(16,16, heartRate, 2);
Serial.print(F(", HRvalid="));
Serial.print(validHeartRate, DEC);
Serial.print(F(", SPO2="));
Serial.print(spo2, DEC);
Serial.print(F(", SPO2Valid="));
Serial.println(validSPO2, DEC);
}
El código completo es el siguiente:
/*
Optical SP02 Detection (SPK Algorithm) using the MAX30105 Breakout
By: Nathan Seidle @ SparkFun Electronics
Date: October 19th, 2016
https://github.com/sparkfun/MAX30105_Breakout
This demo shows heart rate and SPO2 levels.
It is best to attach the sensor to your finger using a rubber band or other tightening
device. Humans are generally bad at applying constant pressure to a thing. When you
press your finger against the sensor it varies enough to cause the blood in your
finger to flow differently which causes the sensor readings to go wonky.
This example is based on MAXREFDES117 and RD117_LILYPAD.ino from Maxim. Their example
was modified to work with the SparkFun MAX30105 library and to compile under Arduino 1.6.11
Please see license file for more info.
Hardware Connections (Breakoutboard to Arduino):
-5V = 5V (3.3V is allowed)
-GND = GND
-SDA = A4 (or SDA)
-SCL = A5 (or SCL)
-INT = Not connected
The MAX30105 Breakout can handle 5V or 3.3V I2C logic. We recommend powering the board with 5V
but it will also run at 3.3V.
*/
#include <Wire.h>
#include "MAX30105.h"
#include "spo2_algorithm.h"
#include <lcdgfx.h>
//Objeto pantalla OLED
int8_t ResetPin = -1; //Cambiar por -1 si no hay pin de reset
int8_t Dir_Pantalla = 0x3C; //Cambiar por 0x3C si esta direccion no funciona
DisplaySSD1306_128x64_I2C display(ResetPin, { - 1, Dir_Pantalla, -1, -1, 0});
//Objeto sensor
MAX30105 particleSensor;
#define MAX_BRIGHTNESS 255
#if defined(__AVR_ATmega328P__) || defined(__AVR_ATmega168__)
//Arduino Uno doesn't have enough SRAM to store 100 samples of IR led data and red led data in 32-bit format
//To solve this problem, 16-bit MSB of the sampled data will be truncated. Samples become 16-bit data.
uint16_t irBuffer[100]; //infrared LED sensor data
uint16_t redBuffer[100]; //red LED sensor data
#else
uint32_t irBuffer[100]; //infrared LED sensor data
uint32_t redBuffer[100]; //red LED sensor data
#endif
int32_t bufferLength; //data length
int32_t spo2; //SPO2 value
int8_t validSPO2; //indicator to show if the SPO2 calculation is valid
int32_t heartRate; //heart rate value
int32_t valor_pulso;
int8_t validHeartRate; //indicator to show if the heart rate calculation is valid
byte pulseLED = 11; //Must be on PWM pin
byte readLED = 13; //Blinks with each data read
int x=0;//Variable de depuración
void setup()
{
Serial.begin(115200); // initialize serial communication at 115200 bits per second:
display.begin();
display.fill(0x00);
x=0;
// display.display();
pinMode(pulseLED, OUTPUT);
pinMode(readLED, OUTPUT);
// Initialize sensor
if (!particleSensor.begin(Wire, I2C_SPEED_FAST)) //Use default I2C port, 400kHz speed
{
Serial.println(F("MAX30105 was not found. Please check wiring/power."));
while (1);
}
Serial.println(F("Attach sensor to finger with rubber band. Press any key to start conversion"));
while (Serial.available() == 0) ; //wait until user presses a key
Serial.read();
byte ledBrightness = 60; //Options: 0=Off to 255=50mA
byte sampleAverage = 4; //Options: 1, 2, 4, 8, 16, 32
byte ledMode = 2; //Options: 1 = Red only, 2 = Red + IR, 3 = Red + IR + Green
byte sampleRate = 100; //Options: 50, 100, 200, 400, 800, 1000, 1600, 3200
int pulseWidth = 411; //Options: 69, 118, 215, 411
int adcRange = 4096; //Options: 2048, 4096, 8192, 16384
particleSensor.setup(ledBrightness, sampleAverage, ledMode, sampleRate, pulseWidth, adcRange); //Configure sensor with these settings
}
void loop()
{
bufferLength = 100; //buffer length of 100 stores 4 seconds of samples running at 25sps
//read the first 100 samples, and determine the signal range
for (byte i = 0 ; i < bufferLength ; i++)
{
while (particleSensor.available() == false) //do we have new data?
particleSensor.check(); //Check the sensor for new data
redBuffer[i] = particleSensor.getRed();
irBuffer[i] = particleSensor.getIR();
particleSensor.nextSample(); //We're finished with this sample so move to next sample
Serial.print(F("red="));
Serial.print(redBuffer[i], DEC);
Serial.print(F(", ir="));
Serial.println(irBuffer[i], DEC);
}
//calculate heart rate and SpO2 after first 100 samples (first 4 seconds of samples)
maxim_heart_rate_and_oxygen_saturation(irBuffer, bufferLength, redBuffer, &spo2, &validSPO2, &heartRate, &validHeartRate);
//Continuously taking samples from MAX30102. Heart rate and SpO2 are calculated every 1 second
while (1)
{
if(x==0){
escribir_texto(0,0,"Hasta aquí llego",1);
}
//dumping the first 25 sets of samples in the memory and shift the last 75 sets of samples to the top
for (byte i = 25; i < 100; i++)
{
redBuffer[i - 25] = redBuffer[i];
irBuffer[i - 25] = irBuffer[i];
}
//take 25 sets of samples before calculating the heart rate.
for (byte i = 75; i < 100; i++)
{
while (particleSensor.available() == false) //do we have new data?
particleSensor.check(); //Check the sensor for new data
digitalWrite(readLED, !digitalRead(readLED)); //Blink onboard LED with every data read
redBuffer[i] = particleSensor.getRed();
irBuffer[i] = particleSensor.getIR();
particleSensor.nextSample(); //We're finished with this sample so move to next sample
//send samples and calculation result to terminal program through UART
Serial.print(F("red="));
Serial.print(redBuffer[i], DEC);
Serial.print(F(", ir="));
Serial.print(irBuffer[i], DEC);
Serial.print(F(", HR="));
Serial.print(heartRate, DEC);
escribir_texto(16,16, heartRate, 2);
Serial.print(F(", HRvalid="));
Serial.print(validHeartRate, DEC);
Serial.print(F(", SPO2="));
Serial.print(spo2, DEC);
Serial.print(F(", SPO2Valid="));
Serial.println(validSPO2, DEC);
}
//After gathering 25 new samples recalculate HR and SP02
maxim_heart_rate_and_oxygen_saturation(irBuffer, bufferLength, redBuffer, &spo2, &validSPO2, &heartRate, &validHeartRate);
}
x++;
}
void escribir_texto(byte x_pos, byte y_pos, char *text, byte text_size) {
display.setFixedFont(ssd1306xled_font6x8);///Seleccionamos una fuente
if (text_size == 1) {
display.printFixed (x_pos, y_pos, text, STYLE_NORMAL);
}
else if (text_size == 2) {
display.printFixedN (x_pos, y_pos, text, STYLE_NORMAL, FONT_SIZE_2X);
}
}
La pantalla OLED la tengo conectada a 5V, y el sensor MAX30102 a 3,3V
Gracias de antemano. Un saludo.