void matrix_init(void)
{
adb_host_init();
+ // wait for keyboard to boot up and receive command
+ _delay_ms(1000);
+ // Enable keyboard left/right modifier distinction
+ // Addr:Keyboard(0010), Cmd:Listen(10), Register3(11)
+ // upper byte: reserved bits 0000, device address 0010
+ // lower byte: device handler 00000011
+ adb_host_listen(0x2B,0x02,0x03);
// initialize matrix state: all keys off
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(16); // 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;
} 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;