diff --git a/src/Row_ShiftRegisters.cpp b/src/Row_ShiftRegisters.cpp
index ebde054..670237e 100644
--- a/src/Row_ShiftRegisters.cpp
+++ b/src/Row_ShiftRegisters.cpp
@@ -4,12 +4,12 @@ void Row_ShiftRegisters::process()
 {
     //these variables are all bitwise, one bit per key
     read_pins_t rowState;                       //1 means pressed, 0 means released
-    uint8_t readPinCount;
+    //uint8_t readPinCount;
     read_pins_t debouncedChanged;               //1 means debounced changed
 
-    rowState = scanner.scan(readPinCount);
+    rowState = scanner.scan();
     debouncedChanged = debouncer.debounce(rowState, debounced);
-    pressRelease(readPinCount, debouncedChanged);
+    pressRelease(READ_PIN_COUNT, debouncedChanged);
 }
 
 void Row_ShiftRegisters::begin()
diff --git a/src/Row_ShiftRegisters.h b/src/Row_ShiftRegisters.h
index d017e36..630b753 100644
--- a/src/Row_ShiftRegisters.h
+++ b/src/Row_ShiftRegisters.h
@@ -30,9 +30,10 @@ class Row_ShiftRegisters : public Row
         Scanner_ShiftRegs74HC165 scanner;
         Debouncer_4Samples debouncer;
         //Debouncer_Not debouncer; //passed test
+        const uint8_t READ_PIN_COUNT;           //number of read pins
     public:
         Row_ShiftRegisters(const uint8_t STROBE_PIN, uint8_t READ_PIN_COUNT, Key *const ptrsKeys[])
-            : Row(ptrsKeys), scanner(STROBE_PIN, READ_PIN_COUNT) { }
+            : Row(ptrsKeys), scanner(STROBE_PIN, READ_PIN_COUNT), READ_PIN_COUNT(READ_PIN_COUNT) { }
         void begin();
         void process();
 };
diff --git a/src/Row_uC.cpp b/src/Row_uC.cpp
index 996bc4d..6855044 100644
--- a/src/Row_uC.cpp
+++ b/src/Row_uC.cpp
@@ -7,10 +7,10 @@ void Row_uC::process()
 {
     //these variables are all bitwise, one bit per key
     read_pins_t rowState;                       //1 means pressed, 0 means released
-    uint8_t readPinCount;
+    //uint8_t readPinCount;
     read_pins_t debouncedChanged;               //1 means debounced changed
 
-    rowState = scanner.scan(readPinCount);
+    rowState = scanner.scan();
     debouncedChanged = debouncer.debounce(rowState, debounced);
-    pressRelease(readPinCount, debouncedChanged);
+    pressRelease(READ_PIN_COUNT, debouncedChanged);
 }
diff --git a/src/Row_uC.h b/src/Row_uC.h
index ca4482c..f269621 100644
--- a/src/Row_uC.h
+++ b/src/Row_uC.h
@@ -31,10 +31,11 @@ class Row_uC : public Row
     private:
         Scanner_uC scanner;
         Debouncer_4Samples debouncer;
+        const uint8_t READ_PIN_COUNT;           //number of read pins
     public:
         Row_uC(const uint8_t strobePin, const uint8_t READ_PINS[], const uint8_t READ_PIN_COUNT,
                 Key *const ptrsKeys[])
-            : Row(ptrsKeys), scanner(strobePin, READ_PINS, READ_PIN_COUNT) { }
+            : Row(ptrsKeys), scanner(strobePin, READ_PINS, READ_PIN_COUNT), READ_PIN_COUNT(READ_PIN_COUNT) { }
         void process();
 };
 #endif
diff --git a/src/Scanner_ShiftRegs74HC165.cpp b/src/Scanner_ShiftRegs74HC165.cpp
index df625a4..656b0b6 100644
--- a/src/Scanner_ShiftRegs74HC165.cpp
+++ b/src/Scanner_ShiftRegs74HC165.cpp
@@ -2,7 +2,7 @@
 
 //constructor
 Scanner_ShiftRegs74HC165::Scanner_ShiftRegs74HC165(const uint8_t STROBE_PIN, uint8_t READ_PIN_COUNT)
-    : STROBE_PIN(STROBE_PIN), BYTE_COUNT(ceil (float(READ_PIN_COUNT)/8)), READ_PIN_COUNT(READ_PIN_COUNT)
+    : STROBE_PIN(STROBE_PIN), BYTE_COUNT(ceil (float(READ_PIN_COUNT)/8))
 {
     //configure controller to communicate with shift register matrix
     pinMode(STROBE_PIN, OUTPUT);
@@ -18,7 +18,7 @@ void Scanner_ShiftRegs74HC165::begin()
 /*
 Sets readPinCount and returns rowState.
 */
-read_pins_t Scanner_ShiftRegs74HC165::scan(uint8_t& readPinCount)
+read_pins_t Scanner_ShiftRegs74HC165::scan()
 {
     read_pins_t rowState = 0;
 
@@ -34,7 +34,7 @@ read_pins_t Scanner_ShiftRegs74HC165::scan(uint8_t& readPinCount)
     //strobe row off
     digitalWrite(STROBE_PIN, STROBE_OFF);
 
-    readPinCount = READ_PIN_COUNT;
+  //  readPinCount = READ_PIN_COUNT;
 
     //for testing on breadboard, clear unpowered pins
     rowState &= 0b11110001000100010001000100010001; //todo
diff --git a/src/Scanner_ShiftRegs74HC165.h b/src/Scanner_ShiftRegs74HC165.h
index 36d3b89..44b57aa 100644
--- a/src/Scanner_ShiftRegs74HC165.h
+++ b/src/Scanner_ShiftRegs74HC165.h
@@ -44,10 +44,10 @@ class Scanner_ShiftRegs74HC165
         static const bool STROBE_OFF;           //logic level of strobe off, complement of active state
         const uint8_t STROBE_PIN;               //Arduino pin number connected to this row
         const uint8_t BYTE_COUNT;               //number of bytes to read from shift registers
-        uint8_t READ_PIN_COUNT;
+        //uint8_t READ_PIN_COUNT;
     public:
         Scanner_ShiftRegs74HC165(const uint8_t STROBE_PIN, uint8_t READ_PIN_COUNT);
-        virtual read_pins_t scan(uint8_t& READ_PIN_COUNT);
+        virtual read_pins_t scan();
         void begin();
 };
 #endif
diff --git a/src/Scanner_uC.cpp b/src/Scanner_uC.cpp
index 3ac8540..49f3464 100644
--- a/src/Scanner_uC.cpp
+++ b/src/Scanner_uC.cpp
@@ -36,7 +36,7 @@ https://www.arduino.cc/en/Reference/DigitalWrite
 https://www.arduino.cc/en/Reference/DigitalRead
 https://www.arduino.cc/en/Reference/Constants > Digital Pins modes: INPUT, INPUT_PULLUP, and OUTPUT
 */
-read_pins_t Scanner_uC::scan(uint8_t& readPinCount)
+read_pins_t Scanner_uC::scan()
 {
     read_pins_t rowState = 0;                   //bitwise, one col per bit, 1 means key is pressed
     read_pins_t readMask = 1;                   //bitwise, one col per bit, active col bit is 1
@@ -58,6 +58,6 @@ read_pins_t Scanner_uC::scan(uint8_t& readPinCount)
     //strobe row off
     digitalWrite(STROBE_PIN, STROBE_OFF);
 
-    readPinCount = READ_PIN_COUNT;
+   // readPinCount = READ_PIN_COUNT;
     return rowState;
 }
diff --git a/src/Scanner_uC.h b/src/Scanner_uC.h
index 6b76e32..a6d4c44 100644
--- a/src/Scanner_uC.h
+++ b/src/Scanner_uC.h
@@ -19,8 +19,8 @@ class Scanner_uC
         const uint8_t READ_PIN_COUNT;           //number of read pins
     public:
         Scanner_uC(const uint8_t STROBE_PIN,
-                const uint8_t READ_PINS[], const uint8_t READ_PIN_COUNT); //todo rename READ_PIN_COUNT to READ_PIN_COUNT ??
-        virtual read_pins_t scan(uint8_t& READ_PIN_COUNT);
+                const uint8_t READ_PINS[], const uint8_t READ_PIN_COUNT);
+        virtual read_pins_t scan();
 };
 #endif