diff --git a/src/RowScanner_PinsArray.cpp b/src/RowScanner_PinsArray.cpp
index d8aa82e..d51ce46 100644
--- a/src/RowScanner_PinsArray.cpp
+++ b/src/RowScanner_PinsArray.cpp
@@ -2,16 +2,16 @@
 
 /* constructor
 */
-RowScanner_PinsArray::RowScanner_PinsArray(const uint8_t strobePin,
-        const uint8_t readPins[], const uint8_t READ_PIN_COUNT)
-    : strobePin(strobePin), readPins(readPins), READ_PIN_COUNT(READ_PIN_COUNT)
+RowScanner_PinsArray::RowScanner_PinsArray(const uint8_t STROBE_PIN,
+        const uint8_t READ_PINS[], const uint8_t READ_PIN_COUNT)
+    : STROBE_PIN(STROBE_PIN), READ_PINS(READ_PINS), READ_PIN_COUNT(READ_PIN_COUNT)
 {
     uint8_t mode;
 
     //configure row
-    pinMode(strobePin, OUTPUT);
+    pinMode(STROBE_PIN, OUTPUT);
 
-    if (activeHigh)
+    if (ACTIVE_HIGH)
     {
         mode = INPUT;                   //requires external pull-down resistor
     }
@@ -23,7 +23,7 @@ RowScanner_PinsArray::RowScanner_PinsArray(const uint8_t strobePin,
     //configure cols
     for (uint8_t i=0; i < READ_PIN_COUNT; i++)
     {
-        pinMode(readPins[i], mode);
+        pinMode(READ_PINS[i], mode);
     }
 }
 
@@ -45,20 +45,20 @@ read_pins_t RowScanner_PinsArray::scan(read_pins_mask_t& rowEnd)
     rowEnd = 1;
 
     //strobe row on
-    if (activeHigh)
+    if (ACTIVE_HIGH)
     {
-        digitalWrite(strobePin, HIGH);
+        digitalWrite(STROBE_PIN, HIGH);
     }
     else //activeLow
     {
-        digitalWrite(strobePin, LOW);
+        digitalWrite(STROBE_PIN, LOW);
     }
     delayMicroseconds(3);                       //time to stablize voltage
 
     //read all the column pins
     for (uint8_t i=0; i < READ_PIN_COUNT; i++)
     {
-        if ( digitalRead(readPins[i]) == activeHigh )
+        if ( digitalRead(READ_PINS[i]) == ACTIVE_HIGH )
         {
             rowState |= rowEnd;
         }
@@ -66,13 +66,13 @@ read_pins_t RowScanner_PinsArray::scan(read_pins_mask_t& rowEnd)
     }
 
     //strobe row off
-    if (activeHigh)
+    if (ACTIVE_HIGH)
     {
-        digitalWrite(strobePin, LOW);
+        digitalWrite(STROBE_PIN, LOW);
     }
     else //activeLow
     {
-        digitalWrite(strobePin, HIGH);
+        digitalWrite(STROBE_PIN, HIGH);
     }
 
     return rowState;
diff --git a/src/RowScanner_PinsArray.h b/src/RowScanner_PinsArray.h
index b02f055..3f66048 100644
--- a/src/RowScanner_PinsArray.h
+++ b/src/RowScanner_PinsArray.h
@@ -14,13 +14,13 @@ Constructor is in RowScanner_PinsArray.cpp
 class RowScanner_PinsArray : public RowScannerInterface
 {
     private:
-        static const bool activeHigh;           //logic level of strobe pin: 0=activeLow, 1=activeHigh
-        const uint8_t strobePin;                //Arduino pin number connected to this row
-        const uint8_t* readPins;                //array of read pin numbers
+        static const bool ACTIVE_HIGH;          //logic level of strobe pin: 0=activeLow, 1=activeHigh
+        const uint8_t STROBE_PIN;               //Arduino pin number connected to this row
+        const uint8_t* const READ_PINS;               //array of read pin numbers
         const uint8_t READ_PIN_COUNT;           //number of read pins
     public:
-        RowScanner_PinsArray(const uint8_t strobePin,
-                const uint8_t readPins[], const uint8_t READ_PIN_COUNT);
+        RowScanner_PinsArray(const uint8_t STROBE_PIN,
+                const uint8_t READ_PINS[], const uint8_t READ_PIN_COUNT);
         virtual read_pins_t scan(read_pins_mask_t& rowEnd);
         //read_pins_t getRowState(read_pins_mask_t& rowEnd);
 };