EMG Envelop sketch

This updated EMG Envelop code now works for Arduino UNO/NANO, ESP32, and other development boards.

software/EMGEnvelop/EMGEnvelop.ino

@@ -1,6 +1,11 @@
-// EMG Envelop - EXG Pill
+// EMG Envelop - BioAmp EXG Pill
+// https://github.com/upsidedownlabs/BioAmp-EXG-Pill
 
-// Copyright (c) 2021 Upside Down Labs
+// Upside Down Labs invests time and resources providing this open source code,
+// please support Upside Down Labs and open-source hardware by purchasing
+// products from Upside Down Labs!
+
+// Copyright (c) 2021 Upside Down Labs - [email protected]
 
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal
@@ -20,17 +25,17 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
 
-#define SampleRate 500
-#define BaudRate 115200
-#define inputPin A0
-#define BufferSize 128
+#define SAMPLE_RATE 500
+#define BAUD_RATE 115200
+#define INPUT_PIN A0
+#define BUFFER_SIZE 128
 
-int circularBuffer[BufferSize];
-int index, sum;
+int circular_buffer[BUFFER_SIZE];
+int data_index, sum;
 
 void setup() {
 	// Serial connection begin
-	Serial.begin(BaudRate);
+	Serial.begin(BAUD_RATE);
 }
 
 void loop() {
@@ -46,23 +51,23 @@ void loop() {
 
 	// Sample and get envelop
 	if(timer < 0) {
-		timer += 1000000 / SampleRate;
-		int sensorValue = analogRead(inputPin);
-		int EMGSignal = EMGFilter(sensorValue);
-		int envelop = getEnvelop(abs(EMGSignal));
-		Serial.print(EMGSignal);
+		timer += 1000000 / SAMPLE_RATE;
+		int sensor_value = analogRead(INPUT_PIN);
+		int signal = EMGFilter(sensor_value);
+		int envelop = getEnvelop(abs(signal));
+		Serial.print(signal);
 		Serial.print(",");
 		Serial.println(envelop);
 	}
 }
 
 // Envelop detection algorithm
-int getEnvelop(int absEMG){
-	sum -= circularBuffer[index];
-	sum += absEMG;
-	circularBuffer[index] = absEMG;
-	index = (index + 1) % BufferSize;
-	return (sum/BufferSize) * 2;
+int getEnvelop(int abs_emg){
+	sum -= circular_buffer[data_index];
+	sum += abs_emg;
+	circular_buffer[data_index] = abs_emg;
+	data_index = (data_index + 1) % BUFFER_SIZE;
+	return (sum/BUFFER_SIZE) * 2;
 }
 
 // Band-Pass Butterworth IIR digital filter, generated using filter_gen.py.