Linux API/joystick2012.02.04 14:37
CCTV(PTZ) 업체에 있다 보니 리눅스에서도 조이스틱을 이용해서
컨트롤러를 대체할수 있을까 라는 생각에 조이스틱 관련 API를 찾아보는데
의외로 단순한 구조 같은 느낌..

요즘에는 USB로도 많이 쓰니 USB목록에서 장치명을 찾아서 열거하는 것도 필요할 듯 하고
아무튼 중요한건 js_event 구조체 이녀석인듯.
int fd = open ("/dev/js0", O_RDONLY);
struct js_event e;
read (fd, &e, sizeof(struct js_event));

struct js_event {
__u32 time;     /* event timestamp in milliseconds */
__s16 value;    /* value */
__u8 type;      /* event type */
__u8 number;    /* axis/button number */
}; 

[링크 : http://www.mjmwired.net/kernel/Documentation/input/joystick-api.txt] 3.2 kernel
[링크 :  http://archives.seul.org/linuxgames/Aug-1999/msg00107.html] 2.2 kernel

----
curse.h가 없다고 에러날 경우는 아래와 같이 설치해주고
$ sudo apt-get install libncurses5-dev  

소스는 이런식으로 수정하고 컴파일을 하면된다.
#define JOY_DEV "/dev/input/js0"  

#include "pthread.h"
#include "sys/timeb.h"
#include "curses.h"
#include "fcntl.h"
#include "linux/joystick.h"

#define NUM_THREADS	3
#define JOY_DEV		"/dev/input/js0"
#define HZ				12

const char FILENAME[] = "./joystickLog.out";
char axisDesc[15][5] = {"X", "Y", "Z", "R", "A", "B", "C", "D", "E", "F", "G", "H", "I" };
char numAxis[20], numButtons[20], value[20][20], timeSec[20], timeMilli[20];
int num_of_axis;

void write_to_log(){
	sleep(1);
	int cnt;
	FILE * daFile;
	daFile = fopen(FILENAME, "w+");

//	WRITE A HEADER ON THE OUPUT FILE
	fprintf(daFile, "#,");
	for(cnt = 0; cnt < num_of_axis; cnt++)
		if(cnt < num_of_axis -1)	fprintf(daFile, "%s,", axisDesc[cnt]);
		else								fprintf(daFile, "%s", axisDesc[cnt]);
	fprintf(daFile, "\r\n");

	while(1){
		fprintf(daFile, "%s.%s, ", timeSec, timeMilli);
		for(cnt = 0; cnt < num_of_axis; cnt++){
			if(cnt < num_of_axis -1)	fprintf(daFile, "%s, ", value[cnt]);
			else								fprintf(daFile, "%s ", value[cnt]);
		}
		fprintf(daFile, "\r\n");
		usleep(83333);
	}
	
	fprintf(daFile, "%s.%s Len = %d ", timeSec, timeMilli,strlen(timeMilli));

	fprintf(daFile, "\r\n");
	fflush(daFile);
}

void write_to_screen(){
	struct timeb seconds;
	int cnt, joy_fd, *axis=NULL, num_of_buttons=0, x;
	char *button=NULL, name_of_joystick[80];
	struct js_event js;
	time_t theTime;

	wmove(stdscr, 8, 0);
	addstr("Type \"q\" to quit.\n");

	if( ( joy_fd = open( JOY_DEV , O_RDONLY)) == -1 ){
		wmove(stdscr, 3,0);
		addstr( "Couldn't open joystick " );
		addstr( JOY_DEV );
		wmove(stdscr, 10,0);
		while(1)usleep(16666);
	}

	ioctl( joy_fd, JSIOCGAXES, &num_of_axis );				//	GET THE NUMBER OF AXIS ON JS
	ioctl( joy_fd, JSIOCGBUTTONS, &num_of_buttons );		//	GET THE NUMBER OF BUTTONS ON THE JS
	ioctl( joy_fd, JSIOCGNAME(80), &name_of_joystick );	//	GET THE NAME OF THE JS

	axis = (int *) calloc( num_of_axis, sizeof( int ) );
	button = (char *) calloc( num_of_buttons, sizeof( char ) );

	sprintf(numAxis, "%d", num_of_axis);
	sprintf(numButtons, "%d", num_of_buttons);

	wmove(stdscr, 0,0);
	addstr("Joystick detected: ");

	wmove(stdscr, 0, 19);
	addstr(name_of_joystick);

	wmove(stdscr, 1, 0);
	addstr("Number of axis   :");

	wmove(stdscr, 1, 19);
	addstr(numAxis);
	
	wmove(stdscr, 2, 0);
	addstr("Number of buttons:");

	wmove (stdscr, 2, 19);
	addstr(numButtons);

//	CHANGE THE STATUS FLAG OF THE FILE DESCRIPTOR TO NON-BLOCKING MODE
	fcntl( joy_fd, F_SETFL, O_NONBLOCK );   

	while( 1 ){
		usleep(16666);
	
	//	READ THE JOYSTICK STATE, IT WILL BE RETURNED IN THE JS_EVENT STRUCT
		read(joy_fd, &js, sizeof(struct js_event));

	//	GET THE NUMBER OF SECONDS SINCE EPOCH
		ftime(&seconds);
		theTime = time(NULL);
		sprintf(timeSec, "%d", seconds.time);						
		sprintf(timeMilli, "%d", seconds.millitm);
               
	//	CHECK THE EVENT
		switch (js.type & ~JS_EVENT_INIT){
			case JS_EVENT_AXIS:
				axis   [ js.number ] = js.value;
				break;
			case JS_EVENT_BUTTON:
				button [ js.number ] = js.value;
				break;
		}
		//	ADD LEADING 0'S TO THE MILLISECOND STRING (IF NECESSARY)
			char temp[10] = "";
			while(strlen(temp) < (3 - strlen(timeMilli)))
				strcat(temp, "0");
			strcat(temp,timeMilli);
			strcpy(timeMilli, temp);

		//	PRINT THE RESULTS
			wmove(stdscr, 4, 0);
			for(cnt = 0; cnt < num_of_axis; cnt++)
				addstr("            ");
			for(cnt = 0; cnt < num_of_axis && cnt < 13; cnt++){
				sprintf(value[cnt], "%d", axis[cnt]);
				wmove(stdscr, 4, cnt * 10);
				addstr(axisDesc[cnt]);
				addstr(": ");
				wmove(stdscr, 4, (cnt * 10) + 2);
				addstr(value[cnt]);
			}
			
			wmove(stdscr, 6, 0);
			addstr(timeSec);
			wmove(stdscr, 6,10);
			addstr(".");
			wmove(stdscr, 6, 11);
			addstr(timeMilli);
			wmove(stdscr, 6, 15);
			addstr("=");
			wmove(stdscr, 6, 17);
			addstr(ctime(&theTime));
                       
			wmove(stdscr, 10, 0);
			refresh();
	}
}

void *ThreadProcs(void *threadid){
	int thread_id = (int)threadid;
	
	if(thread_id == 0){
		write_to_screen();
	}
	
	if(thread_id == 1){
	//	THIS THREAD WILL MAKE THE PROGRAM EXIT
		int ch;
		nodelay(stdscr, TRUE);				//	SETUP NON BLOCKING INPUT
		while(1) {
			if ((ch = getch()) == ERR) usleep(16666);		//	USER HASN'T RESPONDED
			else if( ch == 'q'){			
				endwin();
				exit(0);			//	QUIT ALL THREADS
			}
		}
	}
	if(thread_id == 2){
		write_to_log();
	}
}

int main(int argc, char *argv[]){
	initscr(); 									//	INIT THE SCREEN FOR CURSES
	pthread_t threads[NUM_THREADS];
	int rc, t;
	for(t = 0; t < NUM_THREADS; t++){	//	MAKE 2 NEW THREADS
		rc = pthread_create(&threads[t], NULL, ThreadProcs, (void *)t);
		if (rc){
			printf("ERROR; return code from pthread_create() is %d\n", rc);
			exit(-1);pthread_exit(NULL);
		}
	}
	
	for(t = 0; t < NUM_THREADS; t++)
		pthread_join(threads[t], NULL);		//	WAIT FOR THREADS TO EXIT OR IT WILL RACE TO HERE.

	endwin();
	return 0;
}


[링크 : http://www.linuxquestions.org/questions/programming-9/joystick-347292/]
 + [링크 : http://sukwoo.blogspot.com/2008/07/ubuntu-804-ncurses.html]
---
[링크 : http://msdn.microsoft.com/en-us/library/windows/desktop/dd743596(v=vs.85).aspx] << 윈도우용

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