do not compile with stack auto, change functions to be nonreentrant, use fixed parameters

- frees up ~4KB of code space

src/key.h

@@ -12,10 +12,23 @@
 extern "C" {
 #endif
 
+#include "utils.h"
+
 //#define DEBUG_KEYS
 
 void KeyInit(void);
-void KeyScan(void);
+
+#pragma nooverlay
+void raw_scan(void) __using(1);
+
+#pragma nooverlay
+void debounce(void) __using(1);
+
+
+#define KeyScan() do { \
+	raw_scan(); \
+	debounce(); \
+} while(0);
 
 #ifdef DEBUG_KEYS
 const uint8_t* DebugGetKeys(void);
@@ -24,7 +37,7 @@ const uint8_t* DebugGetKeys(void);
 //definition included for determining if multiple keys are pressed
 //prefer using GetNewKeys();
 #define TOTAL_ROWS 5
-extern uint8_t Keys[TOTAL_ROWS]; //only bottom nibbles get set
+extern __idata uint8_t Keys[TOTAL_ROWS]; //only bottom nibbles get set
 extern int8_t NewKeyPressed;