ECE 376: Embedded Systems

Homework 10

Questions 1-4

#pragma warning disable 520,1385,1311,1510,1518,2053
#include "piclib.h"

u16_t time = 0;
u32_t capture1_time = 0;
u32_t capture2_time = 0;
u8_t capture2_flag = 0;

void __interrupt() interrupt_handler() {
    if (TMR1IF) {
        time++;
        TMR1IF = 0;
    }

    // PORTA turned on
    if (CCP1IF) {
        capture1_time = ((u32_t)time << 16) | ((u32_t)CCPR1H << 8) | CCPR1L;
        CCP1IF = 0;
    }

    // RB0 pressed
    if (CCP2IF) {
        capture2_time = ((u32_t)time << 16) | ((u32_t)CCPR2H << 8) | CCPR2L;
        capture2_flag = 1;
        CCP2IF = 0;
    }

    timers_end();
}

int main() {
    lcd_init();
    u8_t random = 0;

    TRISA = 0x00;
    TRISB = 0x01;
    TRISC = 0x06;

    TMR1CS = 0;
    T1CON = 0x81;
    TMR1ON = 1;
    TMR1IE = 1;
    TMR1IP = 1;
    TMR1H = 0x00;
    TMR1L = 0x00;

    CCP1CON = 0x05;
    CCP1IE = 1;
    CCP2CON = 0x05;
    CCP2IE = 1;

    while (!RB0) random++;
    while (RB0) random++;

    timers_enable();
    PORTA = 0x00;
    capture2_flag = 0;

    wait(((u16_t) (random % 3)) * 1000 + 4000);

    PORTA = 0xFF;

    while (!capture2_flag);

    u32_t reflex_time = capture2_time - capture1_time;
    lcd_append_all("Reflex time:");
    lcd_goto(1, 0);
    lcd_append_int(reflex_time, 9, 7);

    timers_disable();
    while(1);
}

• Times: [0.2446, 0.1999, 0.1890, 0.247]
• Mean: 0.2201
• Standard Deviation: 0.029995
• 90% Confidence Interval: +- 11.2%

Questions 5-9

#pragma warning disable 520,1385,1311,1510,1518,2053
#include "piclib.h"

#define E4 15169
#define F4 14317

u8_t playing;
u16_t note;

void __interrupt() interrupt_handler() {
    if (CCP1IF) {
        if (playing) RC2 ^= 1;
        CCPR1 += note;
        CCP1IF = 0;
    }
}

void play(u16_t new_note, u16_t milliseconds) {
    note = new_note;
    playing = 1;
    wait(milliseconds);
    playing = 0;
}

int main() {
    TRISC = 0x04;
    PORTC = 0x00;

    TMR1CS = 0;
    T1CON = 0x81;
    TMR1ON = 1;
    TMR1IE = 1;
    TMR1IP = 1;

    CCP1CON = 0x0A;
    CCP1IE = 1;
    CCPR1 = 0;

    timers_enable();
    while (1) {
        play(E4, 500);
        wait(200);
        play(F4, 500);
        wait(1000);
    }
}

#pragma warning disable 520,1385,1311,1510,1518,2053
#include "piclib.h"

#define E4 15169
#define F4 14317

u8_t playing;
u16_t note;

void __interrupt() interrupt_handler() {
    if (CCP1IF) {
        if (playing) RC2 ^= 1;
        CCPR1 += note;
        CCP1IF = 0;
    }
}

void play(u16_t new_note, u16_t milliseconds) {
    note = new_note;
    playing = 1;
    wait(milliseconds);
    playing = 0;
}

int main() {
    TRISB = 0x01;
    TRISC = 0x00;
    PORTC = 0x00;

    TMR1CS = 0;
    T1CON = 0x81;
    TMR1ON = 1;
    TMR1IE = 1;
    TMR1IP = 1;

    CCP1CON = 0x0A;
    CCP1IE = 1;
    CCPR1 = 0;

    timers_enable();
    while (1) {
        while (!RB0);
        while (RB0);

        play(E4, 500);
        wait(200);
        if (TMR1 & 1)
            play(E4, 500);
        else
            play(F4, 500);
        wait(1000);
    }
}

7. 
   #pragma warning disable 520,1385,1311,1510,1518,2053
   #include "piclib.h"

define E4 15169

define F4 14317

u8_t playing; u16_t note;

void __interrupt() interrupt_handler() { if (CCP1IF) { if (playing) RC2 ^= 1; CCPR1 += note; CCP1IF = 0; } }

void play(u16_t new_note, u16_t milliseconds) { note = new_note; playing = 1; wait(milliseconds); playing = 0; }

int main() { TRISB = 0x03; PORTB = 0x00;

TRISC = 0x00;
PORTC = 0x00;

TMR1CS = 0;
T1CON = 0x81;
TMR1ON = 1;
TMR1IE = 1;
TMR1IP = 1;

CCP1CON = 0x0A;
CCP1IE = 1;
CCPR1 = 0;

timers_enable();
u8_t right = 0;
u8_t wrong = 0;
while (1) {
    while (!RB0);
    while (RB0);

    u8_t is_same = TMR1 & 1;

    play(E4, 500);
    wait(200);
    if (is_same)
        play(E4, 500);
    else
        play(F4, 500);
    wait(1000);

    while (!PORTB);
    if ((RB0 && is_same) || (RB1 && !is_same))
        right++;
    else
        wrong++;
    while (PORTB);

    lcd_append_all("Right: ");
    lcd_append_int(right, 1, 0);
    lcd_goto(1, 0);
    lcd_append_all("Wrong: ");
    lcd_append_int(wrong, 1, 0);
}

}

8 & 9.
```c
#pragma warning disable 520,1385,1311,1510,1518,2053
#include "piclib.h"

#define E4 15169
#define E4_LOW 15184 //
#define F4 14317

u8_t playing;
u16_t note;

void __interrupt() interrupt_handler() {
    if (CCP1IF) {
        if (playing) RC2 ^= 1;
        CCPR1 += note;
        CCP1IF = 0;
    }
}

void play(u16_t new_note, u16_t milliseconds) {
    note = new_note;
    playing = 1;
    wait(milliseconds);
    playing = 0;
}

int main() {
    TRISB = 0x03;
    PORTB = 0x00;

    TRISC = 0x00;
    PORTC = 0x00;

    TMR1CS = 0;
    T1CON = 0x81;
    TMR1ON = 1;
    TMR1IE = 1;
    TMR1IP = 1;

    CCP1CON = 0x0A;
    CCP1IE = 1;
    CCPR1 = 0;

    timers_enable();
    u8_t right = 0;
    u8_t wrong = 0;
    while (1) {
        while (!RB0);
        while (RB0);

        u8_t is_same = TMR1 & 1;

        play(E4, 500);
        wait(200);
        if (is_same)
            play(E4, 500);
        else
            play(E4_LOW, 500); //
        wait(1000);

        while (!PORTB);
        if ((RB0 && is_same) || (RB1 && !is_same))
            right++;
        else
            wrong++;
        while (PORTB);

        lcd_append_all("Right: ");
        lcd_append_int(right, 1, 0);
        lcd_goto(1, 0);
        lcd_append_all("Wrong: ");
        lcd_append_int(wrong, 1, 0);
    }
}

• Right => 6
• Wrong => 5

Number of Bins: 2

Probability of Rejection: 68.336%(Guessing)