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