diff --git a/include/engine/Port.hpp b/include/engine/Port.hpp
index ac92e42f..c0be5649 100644
--- a/include/engine/Port.hpp
+++ b/include/engine/Port.hpp
@@ -40,41 +40,41 @@ struct Port {
 	};
 
 	/** Sets the voltage of the given channel. */
-	void setVoltage(float voltage, int channel = 0) {
+	void setVoltage(float voltage, uint8_t channel = 0) {
 		voltages[channel] = voltage;
 	}
 
 	/** Returns the voltage of the given channel.
 	Because of proper bookkeeping, all channels higher than the input port's number of channels should be 0V.
 	*/
-	float getVoltage(int channel = 0) {
+	float getVoltage(uint8_t channel = 0) {
 		return voltages[channel];
 	}
 
 	/** Returns the given channel's voltage if the port is polyphonic, otherwise returns the first voltage (channel 0). */
-	float getPolyVoltage(int channel) {
+	float getPolyVoltage(uint8_t channel) {
 		return isMonophonic() ? getVoltage(0) : getVoltage(channel);
 	}
 
 	/** Returns the voltage if a cable is connected, otherwise returns the given normal voltage. */
-	float getNormalVoltage(float normalVoltage, int channel = 0) {
+	float getNormalVoltage(float normalVoltage, uint8_t channel = 0) {
 		return isConnected() ? getVoltage(channel) : normalVoltage;
 	}
 
-	float getNormalPolyVoltage(float normalVoltage, int channel) {
+	float getNormalPolyVoltage(float normalVoltage, uint8_t channel) {
 		return isConnected() ? getPolyVoltage(channel) : normalVoltage;
 	}
 
 	/** Returns a pointer to the array of voltages beginning with firstChannel.
 	The pointer can be used for reading and writing.
 	*/
-	float* getVoltages(int firstChannel = 0) {
+	float* getVoltages(uint8_t firstChannel = 0) {
 		return &voltages[firstChannel];
 	}
 
 	/** Copies the port's voltages to an array of size at least `channels`. */
 	void readVoltages(float* v) {
-		for (int c = 0; c < channels; c++) {
+		for (uint8_t c = 0; c < channels; c++) {
 			v[c] = voltages[c];
 		}
 	}
@@ -83,14 +83,14 @@ struct Port {
 	Remember to set the number of channels *before* calling this method.
 	*/
 	void writeVoltages(const float* v) {
-		for (int c = 0; c < channels; c++) {
+		for (uint8_t c = 0; c < channels; c++) {
 			voltages[c] = v[c];
 		}
 	}
 
 	/** Sets all voltages to 0. */
 	void clearVoltages() {
-		for (int c = 0; c < channels; c++) {
+		for (uint8_t c = 0; c < channels; c++) {
 			voltages[c] = 0.f;
 		}
 	}
@@ -98,7 +98,7 @@ struct Port {
 	/** Returns the sum of all voltages. */
 	float getVoltageSum() {
 		float sum = 0.f;
-		for (int c = 0; c < channels; c++) {
+		for (uint8_t c = 0; c < channels; c++) {
 			sum += voltages[c];
 		}
 		return sum;
@@ -116,7 +116,7 @@ struct Port {
 		}
 		else {
 			float sum = 0.f;
-			for (int c = 0; c < channels; c++) {
+			for (uint8_t c = 0; c < channels; c++) {
 				sum += std::pow(voltages[c], 2);
 			}
 			return std::sqrt(sum);
@@ -124,27 +124,27 @@ struct Port {
 	}
 
 	template <typename T>
-	T getVoltageSimd(int firstChannel) {
+	T getVoltageSimd(uint8_t firstChannel) {
 		return T::load(&voltages[firstChannel]);
 	}
 
 	template <typename T>
-	T getPolyVoltageSimd(int firstChannel) {
+	T getPolyVoltageSimd(uint8_t firstChannel) {
 		return isMonophonic() ? getVoltage(0) : getVoltageSimd<T>(firstChannel);
 	}
 
 	template <typename T>
-	T getNormalVoltageSimd(T normalVoltage, int firstChannel) {
+	T getNormalVoltageSimd(T normalVoltage, uint8_t firstChannel) {
 		return isConnected() ? getVoltageSimd<T>(firstChannel) : normalVoltage;
 	}
 
 	template <typename T>
-	T getNormalPolyVoltageSimd(T normalVoltage, int firstChannel) {
+	T getNormalPolyVoltageSimd(T normalVoltage, uint8_t firstChannel) {
 		return isConnected() ? getPolyVoltageSimd<T>(firstChannel) : normalVoltage;
 	}
 
 	template <typename T>
-	void setVoltageSimd(T voltage, int firstChannel) {
+	void setVoltageSimd(T voltage, uint8_t firstChannel) {
 		voltage.store(&voltages[firstChannel]);
 	}
 
@@ -153,13 +153,13 @@ struct Port {
 	If disconnected, this does nothing (`channels` remains 0).
 	If 0 is given, `channels` is set to 1 but all voltages are cleared.
 	*/
-	void setChannels(int channels) {
+	void setChannels(uint8_t channels) {
 		// If disconnected, keep the number of channels at 0.
 		if (this->channels == 0) {
 			return;
 		}
 		// Set higher channel voltages to 0
-		for (int c = channels; c < this->channels; c++) {
+		for (uint8_t c = channels; c < this->channels; c++) {
 			voltages[c] = 0.f;
 		}
 		// Don't allow caller to set port as disconnected