Connecting SparkFun MicroPressure Sensor and SDP800 to SparkFun QwiicBus Enpoint to Arduino (nan)

Qwiic System
1

Hello,

I am wondering if I am missing anything with respect to hookup of the SparkFun MicroPressure Sensor.

Currently, I have the sensors routed in this configuration:

image
image1540×341 6.41 KB

My flow sensor (Sensirion SDP800) is working perfectly, however I am having issues with the MicroPressure sensor.

Both sensors successfully initialize, and both come up on the I2C scanner. However, unlike the SDP800, after initializing, the MicroPressure Sensor returns “nan” for a pressure reading.

Do I need to sever I2C connections? I tried cutting both (lines?) on either side of the middle square in the I2C box on the back of the sensor with a box cutter to no avail. Is my sensor defective? It was working for a moment in this configuration before throwing the “nan” reading after second hookup.

I have ensured both sensors are running on 3.3v on the Arduino, and am running a simple Arduino sketch to test:

#include <Wire.h>

#include “SparkFun_MicroPressure.h”

SparkFun_MicroPressure mps;
void setup() {
Serial.begin(9600);
Wire.begin();
if (!mps.begin()) {
Serial.println(“Pressure sensor initialization failed”);
while (1);
}
Serial.println(“Sensor initialized”);
}
void loop() {
float pressure = mps.readPressure(KPA);
Serial.print(“Pressure: “);
Serial.print(pressure);
Serial.println(” kPa”);
delay(1000);
}

All troubleshooting help is appreciated. I have more MicroPressure sensors arriving tomorrow in case I fried this one somehow.

UPDATE: Upon further investigation, both the math saturation and integrity flags are being raised.

How can this be reset, or fixed? OR how can I prevent this from happening again on a new sensor?

3

Do they work connected directly to the Uno?
Do they work when individually connected to the Uno?

4

The sensor used to work directly with the Arduino. After configuring in the manner shown in the image, the sensor stopped working “nan error” both in that configuration and when directly connected to the Arduino. I then cut the pull up resistors on the back with an exacto knife and still get “Nan” error when in the above configuration and when I directly connect to Arduino.