deviceAlpha.h

/*
 * deviceAlpha.h -- PC simulator for the Seneca "Device Alpha" board
 *
 * This header lets lab8.c compile and run on a normal computer (no
 * hardware needed).  It prints what the board would do:
 *   - LED / HEATER / BUZZER state changes are printed as [SIM] messages
 *   - the 7-Segment display is printed as [7SEG] messages
 *   - GetTemperature() returns a realistic value that rises while the
 *     heater is on, with a little random noise
 *   - GetPushButtonState() automatically simulates a press-then-release
 *     after a few polls, so the wait loops behave like a real button
 *
 * On the real lab computer, delete this file and include the official
 * deviceAlpha.h that comes with the Device Alpha software instead;
 * lab8.c itself does not need any change.
 */

#ifndef DEVICE_ALPHA_H
#define DEVICE_ALPHA_H

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#ifdef _WIN32
#include <windows.h>
#else
#include <unistd.h>
#endif

/* ---- device identifiers ---- */
#define BLUE_LED	0
#define GREEN_LED	1
#define YELLOW_LED	2
#define RED_LED		3

#define HEATER		0
#define BUZZER		0
#define TEMPERATURE_SENSOR 0
#define ANY_PUSHBUTTON	0

/* ---- states ---- */
#define OFF		0
#define ON		1
#define RELEASED	0
#define PRESSED		1

static const char *simLedNames[] = { "BLUE", "GREEN", "YELLOW", "RED" };
static int simHeaterOn = 0;
static double simTemperature = 21.0;	/* room temperature at start */

static void SetLEDState(int led, int state)
{
	printf("        [SIM] %s LED %s\n", simLedNames[led], state == ON ? "ON" : "OFF");
}

static void SetHeaterState(int heater, int state)
{
	(void)heater;
	simHeaterOn = (state == ON);
	printf("        [SIM] HEATER %s\n", state == ON ? "ON" : "OFF");
}

static void SetBuzzerState(int buzzer, int state)
{
	(void)buzzer;
	printf("        [SIM] BUZZER %s\n", state == ON ? "ON" : "OFF");
}

static void DisplayIntValue(int value)
{
	printf("        [7SEG] %d\n", value);
}

static void DisplayDoubleValue(double value, int decimals)
{
	printf("        [7SEG] %.*f\n", decimals, value);
}

static void Wait(int milliseconds)
{
#ifdef _WIN32
	Sleep(milliseconds);
#else
	usleep((useconds_t)milliseconds * 1000);
#endif
}

static double GetTemperature(int sensor)
{
	(void)sensor;
	if (simTemperature < 45.0 && simHeaterOn)
		simTemperature += 0.35;	/* heater warms things up */
	/* add a little sensor noise: -0.25 .. +0.25 degrees */
	return simTemperature + ((rand() % 51) - 25) / 100.0;
}

/*
 * Simulated push button: stays RELEASED for the first few polls, then
 * PRESSED for a few polls, then RELEASED again -- exactly the sequence
 * the press-and-release wait loops in lab8.c expect.
 */
static int GetPushButtonState(int button)
{
	static int pollCount = 0;

	(void)button;
	if (pollCount == 0)
		printf("        [SIM] (waiting for a button... auto-pressing)\n");
	pollCount++;
	Wait(30);
	return (pollCount % 8 < 4) ? RELEASED : PRESSED;
}

#endif /* DEVICE_ALPHA_H */