Difference between revisions of "U23 2008-2/Gruppe4"

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Line 1: Line 1:
−
==Mitglieder==
+
== Mitglieder ==
−
* gammlaa (Christian)
+
* Christian
 +
* Steffen
 +
* Stefan
 +
* Martin
  
−
==Code==
+
== 1. Projektabend (20. Oktober) ==
−
===Abend 1===
+
=== Aufgabe ===
−
===Abend 2===
+
Eine LED soll zum leuchten gebracht werden.
−
===Abend 3===
 
  
  
−
[[Category:U23 2008-2]]
+
'''Code:'''
 +
<source lang ="c">
 +
 
 +
#include <avr/io.h>
 +
 +
int main(void)
 +
{
 +
  /* PC4 als Ausgang konfig. */
 +
  DDRC = &b10000;
 +
 +
  /* PC4 auf high setzen */
 +
  PORTC = &b10000;
 +
 +
  /* Endlosschleife */
 +
  while(1){
 +
  }
 +
}
 +
 
 +
</source>
 +
 
 +
 
 +
=== Aufgabe zur Vorbereitung ===
 +
Eine LED Sequenz
 +
 
 +
 
 +
'''Code:'''
 +
<source lang ="c">
 +
#include <avr/io.h>
 +
#include <util/delay.h>
 +
 +
static void led_ausgabe(uint8_t led, uint16_t zeit);
 +
 +
 +
int main(void)
 +
{
 +
  uint16_t  anzeigedauer = 1000;
 +
 +
  /* Ausgaenge konfig. */
 +
 +
  DDRC = (1 << DDC4);
 +
  DDRD = (1 << DDD3) | (1 << DDD6) | (1 << DDD7);
 +
 +
 +
  /* Animation */
 +
  while(1){
 +
  led_ausgabe (0b1000,anzeigedauer);
 +
  led_ausgabe (0b0100,anzeigedauer);
 +
  led_ausgabe (0b0010,anzeigedauer);
 +
  led_ausgabe (0b0001,anzeigedauer);
 +
  }
 +
}
 +
 
 +
 
 +
static void led_ausgabe(uint8_t led, uint16_t zeit) {
 +
  if (led & 0b1){
 +
    PORTC |= (1 << DDC4); }
 +
    else{
 +
      PORTC &= ~(1 << DDC4);}
 +
 
 +
  if (led & 0b10){
 +
    PORTD |= (1 << DDD3);}
 +
    else{
 +
      PORTD &= ~(1 << DDD3);}
 +
 +
  if (led & 0b100){
 +
    PORTD |= (1 << DDD6);}
 +
    else{
 +
      PORTD &= ~(1 << DDD6);}
 +
 +
  if (led & 0b1000){
 +
    PORTD |= (1 << DDD7);}
 +
    else{
 +
      PORTD &= ~(1 << DDD7);}
 +
 
 +
  _delay_ms(zeit);
 +
 
 +
}
 +
</source>
 +
 
 +
== 2. Projektabend (27. Oktober) ==
 +
[http://www.sprut.de/electronic/ir/rc5.htm IR RC-5 Aufbau]
 +
=== Aufgabe ===
 +
 
 +
 
 +
 
 +
'''Code:'''
 +
<source lang ="c">
 +
#include <avr/io.h>
 +
#include <string.h>
 +
#include <stdio.h>
 +
#include <avr/pgmspace.h>
 +
#include "uart.h"
 +
 
 +
static void zeitmessen();
 +
 
 +
int main(void)
 +
{
 +
    uint8_t status;
 +
    status = 0;
 +
 
 +
    /* initialize serial uart */
 +
    uart_init();
 +
 
 +
    /* configure irrx as input */
 +
    DDRC &= ~_BV(PC3);
 +
 
 +
    /* init led pin as output */
 +
    DDRD |= _BV(PD3);
 +
   
 +
   
 +
 
 +
    while(1) {
 +
        /* if ir rx is high, turn off led */
 +
        if (PINC & _BV(PC3))
 +
{
 +
        /* if ir was on, display "aus" to indicate it's been turned off */
 +
if (status==1)
 +
    {
 +
uart_printf("aus");
 +
status=0;
 +
    }
 +
 +
    PORTD &= ~_BV(PD3);
 +
}
 +
else
 +
{
 +
    /* if ir was off, display "an" to indicate it's been turned on */
 +
if (status==0)
 +
    {
 +
uart_printf("an");
 +
status=1;
 +
    }
 +
 
 +
PORTD |= _BV(PD3);
 +
}
 +
    }
 +
}
 +
 
 +
/* static void zeitmessen()
 +
{
 +
 +
}
 +
*/
 +
</source>
 +
 
 +
 
 +
Unser Ergebnis vom 2. Abend: das Programm fragt den Infrarot Empfänger ab, und gibt über die Schnittstelle eine Meldung aus, wenn sich der Zustand ändert.
 +
 
 +
=== Aufgabe zur Vorbereitung ===
 +
 
 +
 
 +
 
 +
'''Code:'''
 +
<source lang ="c">
 +
</source>
 +
 
 +
== 3. Projektabend (03. November) ==
 +
=== Aufgabe ===
 +
 
 +
 
 +
 
 +
'''Code:'''
 +
<source lang ="c">
 +
#include <stdio.h>
 +
#include <stdlib.h>
 +
 
 +
int zahlengen( int a, int e)
 +
{
 +
    double r = e - a + 1;
 +
    return (a + (int)(r * rand() /(RAND_MAX+1.0)));
 +
}
 +
 
 +
int main(void) {
 +
srand(time(0)); //Seed initialisieren
 +
int min=1, max=7,i=0;
 +
for(i=0;i<=100;i++){
 +
printf("%i\n",zahlengen(min,max));}
 +
getchar();
 +
return EXIT_SUCCESS;
 +
}
 +
</source>
 +
 
 +
=== Aufgabe zur Vorbereitung ===
 +
 
 +
 
 +
 
 +
'''Code:'''
 +
<source lang ="c">
 +
</source>
 +
 
 +
 
 +
== 4. Projektabend (10. November) ==
 +
=== Aufgabe ===
 +
 
 +
Um den Jammer zu realisieren, haben wir die folgenden beiden Interrupts aus dem vorgegebenen Code geändert geändert:
 +
 
 +
 
 +
'''Code:'''
 +
 
 +
<source lang ="c">
 +
 
 +
ISR(PCINT1_vect)
 +
100 {
 +
101    /* do nothing if we are just processing a code in the main loop,
 +
102      * or no more space is available for a timer value */
 +
103    if (done || pos == MAX)
 +
104        return;
 +
105
 +
106    /* if this would be the first timing value ever recorded, and the
 +
107      * state before was high (=idle), do not record the timing value
 +
108      * and just reset the timer */
 +
109    if (state && pos == 0) {
 +
110        TCNT1 = 0;
 +
111    /* else record the timing value */
 +
112    } else {
 +
113        /* store current timer value in code[]
 +
114          * and reset the timer */
 +
115        code[pos++] = TCNT1;
 +
116        TCNT1 = 0;
 +
117    }
 +
118
 +
119    if (mode == MODE_JAM)
 +
120    {
 +
121        if (pos % 3 == 0)
 +
122        {
 +
123            /* turn off interrupt */
 +
124            PCICR &= ~_BV(PCIE1);
 +
125            /* change interrupt trigger value to 2 * last timing */
 +
126            OCR1A = (code[pos-1] * 2);
 +
127            /* set TIMER1 to 0 to count jam time */
 +
128            TCNT1 = 0;
 +
129            /* turn on ir */
 +
130            ir_enable(PWM_FREQ);           
 +
131        }
 +
132    }
 +
 
 +
 
 +
 
 +
/* timer 1 compare A interrupt service function */
 +
145 ISR(TIMER1_COMPA_vect)
 +
146 {
 +
147    /* do nothing if we are just processing a code in the main loop */
 +
148    if (done)
 +
149        return;
 +
150
 +
151    /* if some code has been received */
 +
152    if (pos > 0) {
 +
153        /* if pos is odd, one last 'off'-timing is missing, fill with zero */
 +
154        if (pos % 2 == 1)
 +
155            code[pos++] = 0;
 +
156
 +
157        /* signal main */
 +
158        done = 1;
 +
159
 +
160        /* turn on third led */
 +
161        PORTD |= _BV(PD6);
 +
162    }
 +
163
 +
164    if (mode == MODE_JAM)
 +
165    {
 +
166        /* turn off ir */
 +
167        ir_disable();
 +
168        /* reset interrupt trigger */
 +
169        OCR1A = F_CPU/5/64;
 +
170        /* reset TIMER1 */
 +
171        TCNT1 = 0;
 +
172        /* turn on interrrupt */
 +
173        PCICR |= _BV(PCIE1);
 +
174    }
 +
175 }
 +
 
 +
 
 +
</source>
 +
 
 +
=== Aufgabe zur Vorbereitung ===
 +
 
 +
 
 +
 
 +
'''Code:'''
 +
<source lang ="c">
 +
</source>
 +
 
 +
 
 +
== 5. Projektabend (17. November) ==
 +
=== Aufgabe ===
 +
 
 +
 
 +
 
 +
'''Code:'''
 +
<source lang ="c">
 +
#include <avr/io.h>
 +
#include <string.h>
 +
#include <stdio.h>
 +
#include <avr/pgmspace.h>
 +
#include <avr/interrupt.h>
 +
 
 +
#include "uart.h"
 +
 
 +
volatile uint8_t data[100];
 +
volatile uint8_t pos = 0;
 +
volatile uint8_t bit = 0;
 +
 
 +
enum {
 +
    IDLE = 0,
 +
    HEADER_ON = 1,
 +
    HEADER_OFF = 2,
 +
    DATA_HIGH = 3,
 +
    DATA_LOW = 4,
 +
    DONE = 5,
 +
} state = IDLE;
 +
 
 +
static void reset_irrx(void)
 +
{
 +
    state = IDLE;
 +
    pos = 0;
 +
    bit = 0;
 +
    data[0] = 0;
 +
}
 +
 
 +
 
 +
ISR(PCINT1_vect) {
 +
    uint16_t value = TCNT1;
 +
    TCNT1 = 0;
 +
 
 +
    if (state == IDLE) {
 +
        state = HEADER_ON;
 +
    } else if (state == HEADER_ON) {
 +
        /* check if header on is ~9ms */
 +
        if (value >= 2500 && value <= 3300) {
 +
            state = HEADER_OFF;
 +
        } else {
 +
            reset_irrx();
 +
        }
 +
    } else if (state == HEADER_OFF) {
 +
        /* check if header off is ~4.5ms */
 +
        if (value >= 1000 && value <= 1800) {
 +
            state = DATA_HIGH;
 +
        } else {
 +
            uart_printf("r%u %u\n",state,value);
 +
            reset_irrx();
 +
        }
 +
    } else if (state == DATA_HIGH) {
 +
        /* check if data1 is ~560us */
 +
        if (value >= 140 && value <= 270) {
 +
            state = DATA_LOW;
 +
        } else {
 +
            uart_printf("r%u %u\n",state,value);
 +
            reset_irrx();
 +
        }
 +
    } else if (state == DATA_LOW) {
 +
        state = DATA_HIGH;
 +
 
 +
        /* check if data1 is ~560us -> value = 0 */
 +
        if (value >= 140 && value <= 260) {
 +
            bit++;
 +
        }
 +
        /* check if data2 is ~1690us -> value = 1 */
 +
        else if (value >= 400 && value <= 600) {
 +
            data[pos] |= _BV(bit);
 +
            bit++;
 +
        } else {
 +
            uart_printf("r%u %u\n",state,value);
 +
            reset_irrx();
 +
        }
 +
 
 +
        if (bit == 8)
 +
        {
 +
            pos++;
 +
            data[pos + 0] = 0;
 +
            data[pos + 1] = 0;
 +
            bit = 0;
 +
        }
 +
 
 +
    }
 +
}
 +
 
 +
ISR(TIMER1_COMPA_vect)
 +
{
 +
    TCNT1 = 0;
 +
    if (state == DONE || state == IDLE)
 +
      return;
 +
 
 +
    if (pos > 0)
 +
    {
 +
        state = DONE;
 +
    } else {
 +
        reset_irrx();
 +
    }
 +
 +
}
 +
 
 +
int main(void)
 +
{
 +
    /* initialize serial uart */
 +
    uart_init();
 +
 
 +
    uart_printf("booting\n");
 +
 
 +
    /* configure irrx as input */
 +
    DDRC &= ~_BV(PC3);
 +
 
 +
    /* init led pin as output */
 +
    DDRD |= _BV(PD3);
 +
 
 +
    /* configure ir input pin, with pullup */
 +
    DDRC &= ~_BV(PC3);
 +
    PORTC |= _BV(PC3);
 +
 
 +
    /* wait until pin is high (no ir carrier is detected) */
 +
    while(!(PINC & _BV(PC3)));
 +
 
 +
    /* enable pin change interrupt 1 for ir input pin (PC3/PCINT11) */
 +
    PCMSK1 |= _BV(PCINT11);
 +
    PCICR |= _BV(PCIE1);
 +
 
 +
    /* configure timer1 with prescaler 64 and CTC for measuring ir timings */
 +
    TCCR1B = _BV(CS11) | _BV(CS10) | _BV(WGM12);
 +
    /* configure timer action */
 +
    OCR1A = 4800;
 +
    /* enable OCR1A interrupt */
 +
    TIMSK1 = _BV(OCIE1A);
 +
 
 +
    sei();
 +
 
 +
    while(1) {
 +
        /* if ir rx is high, turn off led */
 +
        if (PINC & _BV(PC3)) {
 +
            PORTD &= ~_BV(PD3);
 +
        } else {
 +
            PORTD |= _BV(PD3);
 +
        }
 +
 
 +
        if (state == DONE)
 +
        {
 +
            uart_printf("->%s\n",data);
 +
            reset_irrx();
 +
        }
 +
 
 +
    }
 +
}
 +
</source>
 +
 
 +
=== Aufgabe zur Vorbereitung ===
 +
 
 +
 
 +
 
 +
'''Code:'''
 +
<source lang ="c">
 +
</source>
 +
 
 +
 
 +
== 6. Projektabend (24. November) ==
 +
=== Aufgabe ===
 +
 
 +
 
 +
 
 +
'''Code:'''
 +
<source lang ="c">
 +
</source>
 +
 
 +
 
 +
=== Aufgabe zur Vorbereitung ===
 +
 
 +
 
 +
 
 +
'''Code:'''
 +
<source lang ="c">
 +
</source>
 +
 
 +
 
 +
== Abschlussabend (''vorrausichtlich'' 27. November) ==
 +
Vorstellung der Ergebnisse
 +
 
 +
 
 +
 
 +
[[Category:U23 2008]]

Latest revision as of 17:36, 24 November 2010

Mitglieder

  • Christian
  • Steffen
  • Stefan
  • Martin

1. Projektabend (20. Oktober)

Aufgabe

Eine LED soll zum leuchten gebracht werden.


Code: <source lang ="c">

  1. include <avr/io.h>

int main(void) { 

 /* PC4 als Ausgang konfig. */
 DDRC = &b10000; 

 /* PC4 auf high setzen */
 PORTC = &b10000;

 /* Endlosschleife */
 while(1){
 }

}

</source>


Aufgabe zur Vorbereitung

Eine LED Sequenz


Code: <source lang ="c">

  1. include <avr/io.h>
  2. include <util/delay.h>

static void led_ausgabe(uint8_t led, uint16_t zeit);


int main(void) { 

 uint16_t  anzeigedauer = 1000;

 /* Ausgaenge konfig. */

 DDRC = (1 << DDC4);
 DDRD = (1 << DDD3) | (1 << DDD6) | (1 << DDD7); 


 /* Animation */
 while(1){
 led_ausgabe (0b1000,anzeigedauer);
 led_ausgabe (0b0100,anzeigedauer);
 led_ausgabe (0b0010,anzeigedauer);
 led_ausgabe (0b0001,anzeigedauer);
 }

}


static void led_ausgabe(uint8_t led, uint16_t zeit) { 

 if (led & 0b1){
   PORTC |= (1 << DDC4); }
   else{
     PORTC &= ~(1 << DDC4);}

 if (led & 0b10){
   PORTD |= (1 << DDD3);}
   else{
     PORTD &= ~(1 << DDD3);}

 if (led & 0b100){
   PORTD |= (1 << DDD6);}
   else{
     PORTD &= ~(1 << DDD6);}

 if (led & 0b1000){
   PORTD |= (1 << DDD7);}
   else{
     PORTD &= ~(1 << DDD7);}
  
  _delay_ms(zeit);

} </source>

2. Projektabend (27. Oktober)

IR RC-5 Aufbau

Aufgabe

Code: <source lang ="c">

  1. include <avr/io.h>
  2. include <string.h>
  3. include <stdio.h>
  4. include <avr/pgmspace.h>
  5. include "uart.h"

static void zeitmessen();

int main(void) { 

   uint8_t status;
   status = 0;

   /* initialize serial uart */
   uart_init();

   /* configure irrx as input */
   DDRC &= ~_BV(PC3);

   /* init led pin as output */
   DDRD |= _BV(PD3);
   
   

   while(1) {
       /* if ir rx is high, turn off led */
       if (PINC & _BV(PC3))

{ 

       /* if ir was on, display "aus" to indicate it's been turned off */

if (status==1) { uart_printf("aus"); status=0; }

PORTD &= ~_BV(PD3); } else { /* if ir was off, display "an" to indicate it's been turned on */ if (status==0) { uart_printf("an"); status=1; }

PORTD |= _BV(PD3); } 

   }

}

/* static void zeitmessen() {

}

  • /

</source>


Unser Ergebnis vom 2. Abend: das Programm fragt den Infrarot Empfänger ab, und gibt über die Schnittstelle eine Meldung aus, wenn sich der Zustand ändert.

Aufgabe zur Vorbereitung

Code: <source lang ="c"> </source>

3. Projektabend (03. November)

Aufgabe

Code: <source lang ="c">

  1. include <stdio.h>
  2. include <stdlib.h>

int zahlengen( int a, int e) { 

   double r = e - a + 1;
   return (a + (int)(r * rand() /(RAND_MAX+1.0)));

}

int main(void) { srand(time(0)); //Seed initialisieren int min=1, max=7,i=0; for(i=0;i<=100;i++){ printf("%i\n",zahlengen(min,max));} getchar(); return EXIT_SUCCESS; } </source>

Aufgabe zur Vorbereitung

Code: <source lang ="c"> </source>


4. Projektabend (10. November)

Aufgabe

Um den Jammer zu realisieren, haben wir die folgenden beiden Interrupts aus dem vorgegebenen Code geändert geändert:


Code:

<source lang ="c">

ISR(PCINT1_vect) 100 { 101 /* do nothing if we are just processing a code in the main loop, 102 * or no more space is available for a timer value */ 103 if (done || pos == MAX) 104 return; 105 106 /* if this would be the first timing value ever recorded, and the 107 * state before was high (=idle), do not record the timing value 108 * and just reset the timer */ 109 if (state && pos == 0) { 110 TCNT1 = 0; 111 /* else record the timing value */ 112 } else { 113 /* store current timer value in code[] 114 * and reset the timer */ 115 code[pos++] = TCNT1; 116 TCNT1 = 0; 117 } 118 119 if (mode == MODE_JAM) 120 { 121 if (pos % 3 == 0) 122 { 123 /* turn off interrupt */ 124 PCICR &= ~_BV(PCIE1); 125 /* change interrupt trigger value to 2 * last timing */ 126 OCR1A = (code[pos-1] * 2); 127 /* set TIMER1 to 0 to count jam time */ 128 TCNT1 = 0; 129 /* turn on ir */ 130 ir_enable(PWM_FREQ); 131 } 132 } 


/* timer 1 compare A interrupt service function */

145 ISR(TIMER1_COMPA_vect) 146 { 147 /* do nothing if we are just processing a code in the main loop */ 148 if (done) 149 return; 150 151 /* if some code has been received */ 152 if (pos > 0) { 153 /* if pos is odd, one last 'off'-timing is missing, fill with zero */ 154 if (pos % 2 == 1) 155 code[pos++] = 0; 156 157 /* signal main */ 158 done = 1; 159 160 /* turn on third led */ 161 PORTD |= _BV(PD6); 162 } 163 164 if (mode == MODE_JAM) 165 { 166 /* turn off ir */ 167 ir_disable(); 168 /* reset interrupt trigger */ 169 OCR1A = F_CPU/5/64; 170 /* reset TIMER1 */ 171 TCNT1 = 0; 172 /* turn on interrrupt */ 173 PCICR |= _BV(PCIE1); 174 } 175 }


</source>

Aufgabe zur Vorbereitung

Code: <source lang ="c"> </source>


5. Projektabend (17. November)

Aufgabe

Code: <source lang ="c">

  1. include <avr/io.h>
  2. include <string.h>
  3. include <stdio.h>
  4. include <avr/pgmspace.h>
  5. include <avr/interrupt.h>
  1. include "uart.h"

volatile uint8_t data[100]; volatile uint8_t pos = 0; volatile uint8_t bit = 0;

enum { 

   IDLE = 0,
   HEADER_ON = 1,
   HEADER_OFF = 2,
   DATA_HIGH = 3,
   DATA_LOW = 4,
   DONE = 5,

} state = IDLE;

static void reset_irrx(void) { 

   state = IDLE;
   pos = 0;
   bit = 0;
   data[0] = 0;

}


ISR(PCINT1_vect) { 

   uint16_t value = TCNT1;
   TCNT1 = 0;

   if (state == IDLE) {
       state = HEADER_ON;
   } else if (state == HEADER_ON) {
       /* check if header on is ~9ms */
       if (value >= 2500 && value <= 3300) {
           state = HEADER_OFF;
       } else {
           reset_irrx();
       }
   } else if (state == HEADER_OFF) {
       /* check if header off is ~4.5ms */
       if (value >= 1000 && value <= 1800) {
           state = DATA_HIGH;
       } else {
           uart_printf("r%u %u\n",state,value);
           reset_irrx();
       }
   } else if (state == DATA_HIGH) {
       /* check if data1 is ~560us */
       if (value >= 140 && value <= 270) {
           state = DATA_LOW;
       } else {
           uart_printf("r%u %u\n",state,value);
           reset_irrx();
       }
   } else if (state == DATA_LOW) {
       state = DATA_HIGH;

        /* check if data1 is ~560us -> value = 0 */
       if (value >= 140 && value <= 260) {
           bit++;
       }
       /* check if data2 is ~1690us -> value = 1 */
       else if (value >= 400 && value <= 600) {
           data[pos] |= _BV(bit);
            bit++;
       } else {
           uart_printf("r%u %u\n",state,value);
           reset_irrx();
       }

       if (bit == 8)
       {
           pos++;
           data[pos + 0] = 0;
           data[pos + 1] = 0;
           bit = 0;
       }

   }

}

ISR(TIMER1_COMPA_vect) { 

   TCNT1 = 0;
   if (state == DONE || state == IDLE)
     return;

   if (pos > 0)
   {
       state = DONE;
   } else {
       reset_irrx();
   }

}

int main(void) { 

   /* initialize serial uart */
   uart_init();

   uart_printf("booting\n");

   /* configure irrx as input */
   DDRC &= ~_BV(PC3);

   /* init led pin as output */
   DDRD |= _BV(PD3);

   /* configure ir input pin, with pullup */
   DDRC &= ~_BV(PC3);
   PORTC |= _BV(PC3);

   /* wait until pin is high (no ir carrier is detected) */
   while(!(PINC & _BV(PC3)));

   /* enable pin change interrupt 1 for ir input pin (PC3/PCINT11) */
   PCMSK1 |= _BV(PCINT11);
   PCICR |= _BV(PCIE1);

   /* configure timer1 with prescaler 64 and CTC for measuring ir timings */
   TCCR1B = _BV(CS11) | _BV(CS10) | _BV(WGM12);
   /* configure timer action */
   OCR1A = 4800;
   /* enable OCR1A interrupt */
   TIMSK1 = _BV(OCIE1A);

   sei();

   while(1) {
       /* if ir rx is high, turn off led */
       if (PINC & _BV(PC3)) {
           PORTD &= ~_BV(PD3);
       } else {
           PORTD |= _BV(PD3);
       }

       if (state == DONE)
       {
           uart_printf("->%s\n",data);
           reset_irrx();
       }

   }

} </source>

Aufgabe zur Vorbereitung

Code: <source lang ="c"> </source>


6. Projektabend (24. November)

Aufgabe

Code: <source lang ="c"> </source>


Aufgabe zur Vorbereitung

Code: <source lang ="c"> </source>


Abschlussabend (vorrausichtlich 27. November)

Vorstellung der Ergebnisse

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