tmk_keyboard/usb_keyboard.c

77 行
1.9 KiB
C

#include <avr/interrupt.h>
#include <avr/pgmspace.h>
#include "usb_keyboard.h"
// which modifier keys are currently pressed
// 1=left ctrl, 2=left shift, 4=left alt, 8=left gui
// 16=right ctrl, 32=right shift, 64=right alt, 128=right gui
uint8_t keyboard_modifier_keys=0;
// which keys are currently pressed, up to 6 keys may be down at once
uint8_t keyboard_keys[6]={0,0,0,0,0,0};
// protocol setting from the host. We use exactly the same report
// either way, so this variable only stores the setting since we
// are required to be able to report which setting is in use.
uint8_t keyboard_protocol=1;
// the idle configuration, how often we send the report to the
// host (ms * 4) even when it hasn't changed
uint8_t keyboard_idle_config=125;
// count until idle timeout
uint8_t keyboard_idle_count=0;
// 1=num lock, 2=caps lock, 4=scroll lock, 8=compose, 16=kana
volatile uint8_t keyboard_leds=0;
// perform a single keystroke
int8_t usb_keyboard_press(uint8_t key, uint8_t modifier)
{
int8_t r;
keyboard_modifier_keys = modifier;
keyboard_keys[0] = key;
r = usb_keyboard_send();
if (r) return r;
keyboard_modifier_keys = 0;
keyboard_keys[0] = 0;
return usb_keyboard_send();
}
// send the contents of keyboard_keys and keyboard_modifier_keys
int8_t usb_keyboard_send(void)
{
uint8_t i, intr_state, timeout;
if (!usb_configured()) return -1;
intr_state = SREG;
cli();
UENUM = KEYBOARD_ENDPOINT;
timeout = UDFNUML + 50;
while (1) {
// are we ready to transmit?
if (UEINTX & (1<<RWAL)) break;
SREG = intr_state;
// has the USB gone offline?
if (!usb_configured()) return -1;
// have we waited too long?
if (UDFNUML == timeout) return -1;
// get ready to try checking again
intr_state = SREG;
cli();
UENUM = KEYBOARD_ENDPOINT;
}
UEDATX = keyboard_modifier_keys;
UEDATX = 0;
for (i=0; i<6; i++) {
UEDATX = keyboard_keys[i];
}
UEINTX = 0x3A;
keyboard_idle_count = 0;
SREG = intr_state;
return 0;
}