PULSE OXIMETER AND HEART RATE SENSOR - MAX30101 & MAX32664 and ESP32 thing plus

Sensors Biometrics
1

Hi,

I am trying to hook up an oximeter to a Sparkfun ESP32 thing plus.

I am using the lib from within the Arduino IDE.

if i connect to an Arduino MEGA it works fine, but on the SF thing plus i get an 255 error.

Is this a knows problem?

kind regards,

/Lars

2

Greetings laetes. Thanks for posting on the forums.

I have not heard of this issue before specifically. It sounds like the issue might be with the ESP32 thing plus. Are you able to test the functionality of the pins you are interfacing from the thing to the heart rate sensor by using a different product by chance?

Are there any other variables which are changing such as USB cables, wires, etc? If so, have you tested for breaks in these connections?

3

Hi,

I have tested the following:

  • swapped qwiic cable.

  • swapped oximeter device. ( had a spare)

  • soldered cables and bypassed the qwiic connector, the used this device with the MEGA.

  • turned on a led with digitalwrite on PIN 4 and 5. I am using the pins defined as GPIO4 and GPIO5.

As it worked with the same code on the MEGA i feel quite comfortable with my tests.

4

I just tested on a Adafruit Huzzah ESP8266 and the code works there aswell.

just so i havent made a really stupid misstake,

resPin =4 should be connected to pin marked GPIO4 on pinout diagram

and

mfioPin =5 shouf be connected to pin marked GPIO5on pinout diagram.

right?

/Lars

5

Looking at the Adafruit HUZZAH, pin 4 is SDA and pin 5 is SCL.

According to the pinout for our ESP32 Thing Plus it looks like pin 23 is SDA and 22 is SCL. Perhaps trying to use i2c via these pins instead will fix the issue.

https://cdn.sparkfun.com/assets/learn_t … lusV20.pdf

The reset pin and MFIO pin are hooked up to the Redboard digital I/O pins 4 and 5, respectively. Any GPIO pin on the ESP32 should be able to work as long as the code is modified to reflect which pins you decide to use.

I hope this helps.

6

Hi,

on the ESP32 i am using QWIIC so that should not be an issue.

reset and MFIO are using 4 and 5 but could just be any GPIO pins as you say so i dont think that is the problem.

7

Hey again. Sorry for the delay here.

Hmm, send me a private message with your order details and we can continue from there.

Cheers for now.