FIX: off by one error, when checking key bits

[uccvend-snackrom.git] / ROM2 / keypad.c

diff --git a/ROM2/keypad.c b/ROM2/keypad.c
index 433e78c..0e03095 100644 (file)
--- a/ROM2/keypad.c
+++ b/ROM2/keypad.c
@@ -3,19 +3,24 @@
 #include "keypad.h"
 
 u8 last_key; /* the last key registered */
-bool new_key = 0;
+bool new_key;
 
 /* first 8 from the first row, then 3 from the second row */
 /* keys are 1-9, 0, reset */
 const u8 keymap0[8] = {KEY_8, KEY_7, KEY_6, KEY_5, KEY_4, KEY_3, KEY_2, KEY_1};
 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)
-               _io_ports[M6811_PORTD] |= PORTD_KEYPAD_ROW;
+               bset((void*)&_io_ports[M6811_PORTD], PORTD_KEYPAD_ROW);
        else
-               _io_ports[M6811_PORTD] &= ~PORTD_KEYPAD_ROW;
+               bclr((void*)&_io_ports[M6811_PORTD], PORTD_KEYPAD_ROW);
 
        bclr_misc_output(A3800_DISPLAY_WRITE);  /* disable the display clock */
 
@@ -23,22 +28,25 @@ 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 < 8);
                i=i>>1, num++);
 
        return num;
 }
 
-/* returns a key 1..10 or 11 for reset */
+/* sets last_key to 1..10 or 11 for reset */
 void keypad_read() {
        /* FIXME: need to do debouncing of some sort? */
        u8 key;
        key = keypad_read_row(0);
-       if (!key) {
+       if (NO_KEY == key) {
                key = keypad_read_row(1);
+               if (key <= 2)
+                       key = keymap1[key];
+               else
+                       key = 0;
+       } else
                key = keymap0[key];
-       }
-       key = keymap1[key];
 
        if (key != last_key) {
                last_key = key;
@@ -55,8 +63,7 @@ bool keypad_pressed() {
        return 1;
 }
 
-u8 keypad_getkey() {
-       while (!keypad_pressed())
-               keypad_read();
-       return last_key;
+void keypad_init() {
+       last_key = 0;
+       new_key = 0;
 }