ESP32 and MMA7361 accelerometer example

The MMA7361L is a low power, low profile capacitive micromachined accelerometer featuring signal conditioning, a 1-pole low pass filter, temperature compensation, self test, 0g-Detect which detects linear freefall, and g-Select which allows for the selection between 2 sensitivities. Zero-g offset and sensitivity are factory set and require no external devices. The MMA7361L includes a Sleep Mode that makes it ideal for handheld battery powered electronics.

Features
• 3mm x 5mm x 1.0mm LGA-14 Package
• Low Current Consumption: 400 μA
• Sleep Mode: 3 μA
• Low Voltage Operation: 2.2 V – 3.6 V
• High Sensitivity (800 mV/g @ 1.5g)
• Selectable Sensitivity (±1.5g, ±6g)
• Fast Turn On Time (0.5 ms Enable Response Time)
• Self Test for Freefall Detect Diagnosis
• 0g-Detect for Freefall Protection
• Signal Conditioning with Low Pass Filter
• Robust Design, High Shocks Survivability
• RoHS Compliant
• Environmentally Preferred Product
• Low Cost

Typical Applications
• 3D Gaming: Tilt and Motion Sensing, Event Recorder
• HDD MP3 Player: Freefall Detection
• Laptop PC: Freefall Detection, Anti-Theft
• Cell Phone: Image Stability, Text Scroll, Motion Dialing, E-Compass
• Pedometer: Motion Sensing
• PDA: Text Scroll
• Navigation and Dead Reckoning: E-Compass Tilt Compensation
• Robotics: Motion Sensing

Parts Required

Here are the parts I used

The sensor you can pick up in the $6 price range – you can connect to the sensor using a standard header the classic dupont style jumper wire.

Name	Link
ESP32		Aliexpress link Amazon Ebay
MMA7361		Aliexpress link Ebay link Amazon Link
Connecting cables		Aliexpress link Amazon Ebay

Schematic and connection

esp32 and mma7361

Code

int x;
int y;
int z;

void setup()
{
Serial.begin(9600);
}

void loop()
{
x = analogRead(A4); // read A5 input pin
y = analogRead(A3); // read A4 input pin
z = analogRead(A0); // read A3 input pin
Serial.print("X = "); // print x value
Serial.println(x);
Serial.print("Y = "); // print y value
Serial.println(y);
Serial.print("Z = "); // print z value
Serial.println(z);
delay(1000);
}

Output

Open the serial monitor and move the sensor around, you should see soemthing like this

X = 86
Y = 82
Z = 656
X = 68
Y = 80
Z = 640
X = 76
Y = 80
Z = 657
X = 422
Y = 96
Z = 653
X = 354
Y = 80
Z = 656
X = 1573
Y = 216
Z = 857

Links

http://www.nxp.com/files/sensors/doc/data_sheet/MMA7361L.pdf