usb_keyboard.c

   1 #include <avr/interrupt.h>
   2 #include <avr/pgmspace.h>
   3 #include "usb_keyboard.h"
   4 #include "print.h"
   5
   6
   7 static bool is_sent = false;
   8
   9 // which modifier keys are currently pressed
  10 // 1=left ctrl,    2=left shift,   4=left alt,    8=left gui
  11 // 16=right ctrl, 32=right shift, 64=right alt, 128=right gui
  12 uint8_t keyboard_modifier_keys=0;
  13
  14 // which keys are currently pressed, up to 6 keys may be down at once
  15 uint8_t keyboard_keys[6]={0,0,0,0,0,0};
  16
  17 // protocol setting from the host.  We use exactly the same report
  18 // either way, so this variable only stores the setting since we
  19 // are required to be able to report which setting is in use.
  20 uint8_t keyboard_protocol=1;
  21
  22 // the idle configuration, how often we send the report to the
  23 // host (ms * 4) even when it hasn't changed
  24 uint8_t keyboard_idle_config=125;
  25
  26 // count until idle timeout
  27 uint8_t keyboard_idle_count=0;
  28
  29 // 1=num lock, 2=caps lock, 4=scroll lock, 8=compose, 16=kana
  30 volatile uint8_t keyboard_leds=0;
  31
  32
  33 // perform a single keystroke
  34 int8_t usb_keyboard_press(uint8_t key, uint8_t modifier)
  35 {
  36         int8_t r;
  37
  38         keyboard_modifier_keys = modifier;
  39         keyboard_keys[0] = key;
  40         r = usb_keyboard_send();
  41         if (r) return r;
  42         keyboard_modifier_keys = 0;
  43         keyboard_keys[0] = 0;
  44         return usb_keyboard_send();
  45 }
  46
  47 // send the contents of keyboard_keys and keyboard_modifier_keys
  48 int8_t usb_keyboard_send(void)
  49 {
  50         uint8_t i, intr_state, timeout;
  51
  52         if (!usb_configured()) return -1;
  53         intr_state = SREG;
  54         cli();
  55         UENUM = KEYBOARD_ENDPOINT;
  56         timeout = UDFNUML + 50;
  57         while (1) {
  58                 // are we ready to transmit?
  59                 if (UEINTX & (1<<RWAL)) break;
  60                 SREG = intr_state;
  61                 // has the USB gone offline?
  62                 if (!usb_configured()) return -1;
  63                 // have we waited too long?
  64                 if (UDFNUML == timeout) return -1;
  65                 // get ready to try checking again
  66                 intr_state = SREG;
  67                 cli();
  68                 UENUM = KEYBOARD_ENDPOINT;
  69         }
  70         UEDATX = keyboard_modifier_keys;
  71         UEDATX = 0;
  72         for (i=0; i<6; i++) {
  73                 UEDATX = keyboard_keys[i];
  74         }
  75         UEINTX = 0x3A;
  76         keyboard_idle_count = 0;
  77         SREG = intr_state;
  78         is_sent = true;
  79         return 0;
  80 }
  81
  82 void usb_keyboard_init(void) {
  83     usb_keyboard_clear();
  84     is_sent = false;
  85 }
  86
  87 void usb_keyboard_clear(void) {
  88     usb_keyboard_clear_key();
  89     usb_keyboard_clear_mod();
  90 }
  91
  92 void usb_keyboard_clear_key(void) {
  93     for (int i = 0; i < 6; i++) keyboard_keys[i] = 0;
  94 }
  95
  96 void usb_keyboard_clear_mod(void) {
  97     keyboard_modifier_keys = 0;
  98 }
  99
 100 bool usb_keyboard_is_sent(void) {
 101     return is_sent;
 102 }
 103
 104 bool usb_keyboard_has_key(void) {
 105     uint8_t keys = 0;
 106     for (int i = 0; i < 6; i++) keys |= keyboard_keys[i];
 107     return keys ? true : false;
 108 }
 109
 110 bool usb_keyboard_has_mod(void) {
 111     return keyboard_modifier_keys ? true : false;
 112 }
 113
 114 void usb_keyboard_print(void) {
 115     print("\nkeys: ");
 116     for (int i = 0; i < 6; i++) { phex(keyboard_keys[i]); print(" "); }
 117     print("\n");
 118     print("mods: "); phex(keyboard_modifier_keys); print("\n");
 119 }