view projects/d-box/StatusLED.cpp @ 45:579c86316008 newapi

Major API overhaul. Moved to a single data structure for handling render functions. Functionally, generally similar except for scheduling within PRU loop function, which now uses interrupts from the PRU rather than polling. This requires an updated kernel.

/*
 * StatusLED.cpp
 *
 * Routines for manipulating the status LED
 *
 * (c) 2014 Andrew McPherson and Victor Zappi
 * QMUL, Centre for Digital Music
 */

#include <iostream>
#include "StatusLED.h"
#include "../../include/GPIOcontrol.h"

extern int gShouldStop;
extern int gVerbose;

using namespace std;

StatusLED::StatusLED() {
	gpio_number = -1;
	milliseconds_on = 0;
	milliseconds_off = 100;
	blink_thread = -1;
}

StatusLED::~StatusLED() {
	if(gpio_number >= 0) {
		this_should_stop = true;
		pthread_join(blink_thread, NULL);
		gpio_unexport(gpio_number);
	}
}

bool StatusLED::init(int gpio_pin) {
	gpio_number = gpio_pin;
	this_should_stop = false;

	if(gpio_export(gpio_number)) {
		if(gVerbose)
			cout << "Warning: couldn't export status LED pin\n";
	}
	if(gpio_set_dir(gpio_number, OUTPUT_PIN)) {
		if(gVerbose)
			cout << "Couldn't set direction on status LED pin\n";
		return false;
	}
	if(gpio_set_value(gpio_number, LOW)) {
		if(gVerbose)
			cout << "Couldn't set value on status LED pin\n";
		return false;
	}


	if ( pthread_create(&blink_thread, NULL, static_blink_loop, this) )
	{
		cout << "Error:unable to create status LED thread" << endl;
		return false;
	}

	return true;
}

void StatusLED::on() {
	milliseconds_on = 100;
	milliseconds_off = 0;
}

void StatusLED::off() {
	milliseconds_on = 0;
	milliseconds_off = 100;
}

void StatusLED::blink(int ms_on, int ms_off) {
	milliseconds_on = ms_on;
	milliseconds_off = ms_off;
}

void* StatusLED::blink_loop(void *) {
	while(!gShouldStop && !this_should_stop) {
		if(milliseconds_on != 0)
			gpio_set_value(gpio_number, HIGH);
		usleep(1000 * milliseconds_on);
		if(gShouldStop)
			break;
		if(milliseconds_off != 0)
			gpio_set_value(gpio_number, LOW);
		usleep(1000 * milliseconds_off);
	}
	pthread_exit(NULL);
}