Fixed handling of ADB event with key down and key up for same key all in one

This commit is contained in:
Shay Green 2013-11-26 15:21:43 -06:00
parent 4e36159be2
commit 263c462656
1 changed files with 17 additions and 3 deletions

View File

@ -88,12 +88,26 @@ void matrix_init(void)
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;
@ -113,7 +127,7 @@ uint8_t matrix_scan(void)
} 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;