diff --git a/remoteKeyboard.c b/remoteKeyboard.c
index 34c92c4..bdaa3f3 100644
--- a/remoteKeyboard.c
+++ b/remoteKeyboard.c
@@ -192,6 +192,11 @@ static void assertRowOutputs(row_mask_t mask, row_mask_t polarity)
         else
             PORTB &= ~bits;
     }
+    else
+    {
+    	DDRB &= ~PB_ROW_MASK;	// reset to inputs
+    	PORTB &= ~PB_ROW_MASK;	// and don't pull up
+    }
 #endif
 #if PC_ROW_MASK != 0
     bits = PC_FROM_ROW(mask);
@@ -203,6 +208,11 @@ static void assertRowOutputs(row_mask_t mask, row_mask_t polarity)
         else
             PORTC &= ~bits;
     }
+    else
+    {
+    	DDRC &= ~PC_ROW_MASK;	// reset to inputs
+    	PORTC &= ~PC_ROW_MASK;	// and don't pull up
+    }
 #endif
 #if PD_ROW_MASK != 0
     bits = PD_FROM_ROW(mask);
@@ -214,6 +224,11 @@ static void assertRowOutputs(row_mask_t mask, row_mask_t polarity)
         else
             PORTD &= ~bits;
     }
+    else
+    {
+    	DDRD &= ~PD_ROW_MASK;	// reset to inputs
+    	PORTD &= ~PD_ROW_MASK;	// and don't pull up
+    }
 #endif
 }
 
@@ -389,6 +404,9 @@ ISR(PCINT1_vect)
             }
             break;
 
+        case 0:                // no active column lines
+             break;
+
         case N_COLUMNS - 1:                // quiescent state wrong; one active
             columnInputs ^= quiescentState; // restore flipped bits
             quiescentState = ~quiescentState;
@@ -399,8 +417,6 @@ ISR(PCINT1_vect)
             quiescentState = ~quiescentState;
             break;
 
-        case 0:                // no active column lines
-            break;
     }
 
     // remember last column scan
diff --git a/remoteKeyboard.h b/remoteKeyboard.h
index 9cc1da4..eda5b18 100644
--- a/remoteKeyboard.h
+++ b/remoteKeyboard.h
@@ -76,9 +76,8 @@
 #   define LOG2_N_ROWS 3
 #	define UNUSED_ROWS_MASK		((0xFF<<N_ROWS)&0xFF)
 
-
 #   define PB_ROW_MASK          0x03
-#   define PB_TO_ROW(val)       (((val)&0x03)<<6)
+#   define PB_TO_ROW(val)       (((val)&PB_ROW_MASK)<<6)
 #   define PB_FROM_ROW(val)     ((val)>>6)
 
 #   define PC_ROW_MASK          0x00