X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=converter%2Fadb_usb%2Fmatrix.c;h=405391865fe4861b296320726bd18f3f55c07579;hb=1a02ebcc612e9a9c0d87e02295c7258de3a70ccc;hp=54be2b0f579fcabb4adee319022218f21524d2b6;hpb=c18c52f551545b46a28902c69730eefbdb75577d;p=qmk_firmware.git

diff --git a/converter/adb_usb/matrix.c b/converter/adb_usb/matrix.c
index 54be2b0f5..405391865 100644
--- a/converter/adb_usb/matrix.c
+++ b/converter/adb_usb/matrix.c
@@ -79,21 +79,35 @@ void matrix_init(void)
     for (uint8_t i=0; i < MATRIX_ROWS; i++) matrix[i] = 0x00;
 
     debug_enable = true;
-    debug_matrix = true;
-    debug_keyboard = true;
-    debug_mouse = true;
+    //debug_matrix = true;
+    //debug_keyboard = true;
+    //debug_mouse = true;
     print("debug enabled.\n");
     return;
 }
 
 uint8_t matrix_scan(void)
 {
+    /* extra_key is volatile and more convoluted than necessary because gcc refused
+    to generate valid code otherwise. Making extra_key uint8_t and constructing codes
+    here via codes = extra_key<<8 | 0xFF; would consistently fail to even LOAD
+    extra_key from memory, and leave garbage in the high byte of codes. I tried
+    dozens of code variations and it kept generating broken assembly output. So
+    beware if attempting to make extra_key code more logical and efficient. */
+    static volatile uint16_t extra_key = 0xFFFF;
     uint16_t codes;
     uint8_t key0, key1;
 
     is_modified = false;
-    _delay_ms(12);  // delay for preventing overload of poor ADB keyboard controller
-    codes = adb_host_kbd_recv();
+
+    codes = extra_key;
+    extra_key = 0xFFFF;
+
+    if ( codes == 0xFFFF )
+    {
+        _delay_ms(12);  // delay for preventing overload of poor ADB keyboard controller
+        codes = adb_host_kbd_recv();
+    }
     key0 = codes>>8;
     key1 = codes&0xFF;
 
@@ -108,12 +122,12 @@ uint8_t matrix_scan(void)
     } else if (codes == 0xFFFF) {   // power key release
         register_key(0xFF);
     } else if (key0 == 0xFF) {      // error
-        xprintf("adb_host_kbd_recv: ERROR(%02X)\n", codes);
+        xprintf("adb_host_kbd_recv: ERROR(%d)\n", codes);
         return key1;
     } else {
         register_key(key0);
         if (key1 != 0xFF)       // key1 is 0xFF when no second key.
-            register_key(key1);
+            extra_key = key1<<8 | 0xFF; // process in a separate call
     }
 
     return 1;