Fixed non-terminating logic of keypad decoder.

Removed unused function keypad_getkey()

diff --git a/ROM2/keypad.c b/ROM2/keypad.c
index 23eddb8..8f50c19 100644 (file)
--- a/ROM2/keypad.c
+++ b/ROM2/keypad.c
@@ -12,6 +12,9 @@ const u8 keymap1[3] = {KEY_RESET, KEY_0, KEY_9};
 
 #define        NO_KEY  8
 
+/* reads the keypad and returns the bit number that was turned on in the shift
+ * register (from 0..7). If no bits were turned on, it returns 8 (aka NO_KEY)
+ */
 extern inline u8 keypad_read_row(u8 row) {
        u8 i, num;
        if (row)
@@ -25,7 +28,7 @@ extern inline u8 keypad_read_row(u8 row) {
        while(!(_io_ports[M6811_SPDR]&M6811_SPIE)); /* wait for completion */
 
        for (i = _io_ports[M6811_SPDR], num = 0;
-               (i&0x1) == 0;
+               (i&0x1 == 0) && (num < 7);
                i=i>>1, num++);
 
        return num;
@@ -38,7 +41,10 @@ void keypad_read() {
        key = keypad_read_row(0);
        if (NO_KEY == key) {
                key = keypad_read_row(1);
-               key = keymap1[key];
+               if (key >= 0 && key <= 2)
+                       key = keymap1[key];
+               else
+                       key = 0;
        } else
                key = keymap0[key];
 
@@ -56,9 +62,3 @@ bool keypad_pressed() {
        new_key = 0;
        return 1;
 }
-
-u8 keypad_getkey() {
-       while (!keypad_pressed())
-               keypad_read();
-       return last_key;
-}