1 | /********************************************************************/
|
2 | /* */
|
3 | /* 1LED 1Taster - Entprellung (bessere Version */
|
4 | /* */
|
5 | /* active-low: ein Anschluss an den Port-Pin, der anderer an GND */
|
6 | /* Pull-Up Widerstand (10k) zwischen Port-Pin und VCC. */
|
7 | /* */
|
8 | /* PB0: Taster */
|
9 | /* PD0: LED */
|
10 | /* */
|
11 | /* Datum: 10.10.2010 */
|
12 | /* */
|
13 | /********************************************************************/
|
14 |
|
15 | #include <stdint.h>
|
16 | #include <avr/io.h>
|
17 | #include <avr/interrupt.h>
|
18 |
|
19 | #ifndef F_CPU
|
20 | #define F_CPU 1000000
|
21 | #endif
|
22 |
|
23 | #define KEY_DDR DDRB
|
24 | #define KEY_PORT PORTB
|
25 | #define KEY_PIN PINB
|
26 | #define KEY0 0
|
27 | #define KEY1 1
|
28 | #define KEY2 2
|
29 | #define ALL_KEYS (1<<KEY0 | 1<<KEY1 | 1<<KEY2)
|
30 |
|
31 | #define REPEAT_MASK (1<<KEY1 | 1<<KEY2) // repeat: key1, key2
|
32 | #define REPEAT_START 50 // after 500ms
|
33 | #define REPEAT_NEXT 20 // every 200ms
|
34 |
|
35 | #define LED_DDR DDRD
|
36 | #define LED_PORT PORTD
|
37 | #define LED0 0
|
38 | #define LED1 1
|
39 | #define LED2 2
|
40 |
|
41 | volatile uint8_t key_state;
|
42 | volatile uint8_t key_press;
|
43 | volatile uint8_t key_rpt;
|
44 |
|
45 |
|
46 | ISR( TIMER0_OVF_vect ) { // every 10ms
|
47 | static uint8_t ct0, ct1, rpt;
|
48 | uint8_t i;
|
49 |
|
50 | TCNT0 = (uint8_t)(uint16_t)-(F_CPU / 1024 * 10e-3 + 0.5); // preload for 10ms
|
51 |
|
52 | i = key_state ^ ~KEY_PIN; // Key changed?
|
53 | ct0 = ~( ct0 & i ); // reset or count ct0
|
54 | ct1 = ct0 ^ ( ct1 & i); // reset or count ct1
|
55 | i &= ct0 & ct1;
|
56 | key_state ^= i;
|
57 | key_press |= key_state & i;
|
58 |
|
59 | if( (key_state & REPEAT_MASK) == 0 )
|
60 | rpt = REPEAT_START;
|
61 | if( --rpt == 0 ) {
|
62 | rpt = REPEAT_NEXT; // repeat delay
|
63 | key_rpt |= key_state & REPEAT_MASK;
|
64 | }
|
65 | }
|
66 |
|
67 |
|
68 | // Pr¸fe ob eine Taste gedruekt wurde. Jeder Druck wird als eins gewertet
|
69 | uint8_t get_key_press( uint8_t key_mask ) {
|
70 | cli();
|
71 | key_mask &= key_press;
|
72 | key_press ^= key_mask;
|
73 | sei();
|
74 | return key_mask;
|
75 | }
|
76 |
|
77 | // Pr¸fe ob eine Taste lange genug gedr¸ckt wurde
|
78 | uint8_t get_key_rpt( uint8_t key_mask ) {
|
79 | cli();
|
80 | key_mask &= key_rpt;
|
81 | key_rpt ^= key_mask;
|
82 | sei();
|
83 | return key_mask;
|
84 | }
|
85 |
|
86 | // Pr¸fe ob eine Taste kurz gedr¸ckt wurde
|
87 | uint8_t get_key_short( uint8_t key_mask ) {
|
88 | cli();
|
89 | return get_key_press( ~key_state & key_mask );
|
90 | }
|
91 |
|
92 | // Pr¸fe ob eine Taste lang gedr¸ckt wurde
|
93 | uint8_t get_key_long( uint8_t key_mask ) {
|
94 | cli();
|
95 | return get_key_press( get_key_rpt(key_mask) );
|
96 | }
|
97 |
|
98 |
|
99 |
|
100 | int main(void) {
|
101 | KEY_DDR &= ~ALL_KEYS; // Taste fuer Eingabe
|
102 | KEY_PORT |= ALL_KEYS; // PULL-UP Widerstand An
|
103 |
|
104 |
|
105 | TCCR0 = (1<<CS02)|(1<<CS00); // durch 1024 dividieren
|
106 | TIMSK |= 1<<TOIE0; // Timer-Interrupt aktivieren
|
107 |
|
108 |
|
109 | LED_PORT = 0xFF;
|
110 | LED_DDR = 0xFF;
|
111 |
|
112 | sei();
|
113 |
|
114 | while(1) {
|
115 | if( get_key_short( 1<<KEY0 ) )
|
116 | LED_PORT ^= 1<<LED0;
|
117 |
|
118 | if( get_key_long( 1<<KEY0 ) )
|
119 | LED_PORT ^= 1<<LED1;
|
120 | }
|
121 | }
|
