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/*
* Absolute_Joystick.c
*
* Gameport device absolute joystick example
*
* Compile with SAS 5.10 lc -b1 -cfistq -v -y -L
*
* Run from CLI only
*/
#include <exec/types.h>
#include <exec/io.h>
#include <exec/memory.h>
#include <intuition/intuition.h>
#include <exec/exec.h>
#include <dos/dos.h>
#include <devices/gameport.h>
#include <devices/inputevent.h>
#include <clib/exec_protos.h>
#include <clib/alib_protos.h>
#include <clib/dos_protos.h>
#include <clib/intuition_protos.h>
#include <stdio.h>
#ifdef LATTICE
int CXBRK(void) { return(0); } /* Disable SAS CTRL/C handling */
int chkabort(void) { return(0); } /* really */
#endif
#define JOY_X_DELTA (1)
#define JOY_Y_DELTA (1)
#define TIMEOUT_SECONDS (10)
extern struct ExecBase *SysBase;
/*-----------------------------------------------------------------------
** Routine to print out some information for the user.
*/
VOID printInstructions(VOID)
{
printf("\n >>> gameport.device Absolute Joystick Demo <<<\n\n");
if (SysBase->VBlankFrequency==60)
printf(" Running on NTSC system (60 Hz).\n");
else if (SysBase->VBlankFrequency==50)
printf(" Running on PAL system (50 Hz).\n");
printf(" Attach joystick to rear connector (A3000) and (A1000).\n"
" Attach joystick to right connector (A2000).\n"
" Attach joystick to left connector (A500).\n"
" Then move joystick and click its button(s).\n\n"
" To exit program press and release fire button 3 times in a row.\n"
" The program also exits if no activity occurs for 1 minute.\n\n");
}
/*-----------------------------------------------------------------------
** print out information on the event received.
*/
BOOL check_move(struct InputEvent *game_event)
{
WORD xmove, ymove;
BOOL timeout=FALSE;
xmove = game_event->ie_X;
ymove = game_event->ie_Y;
if (xmove == 1)
{
if (ymove == 1) printf("RIGHT DOWN\n");
else if (ymove == 0) printf("RIGHT\n");
else if (ymove ==-1) printf("RIGHT UP\n");
else printf("UNKNOWN Y\n");
}
else if (xmove ==-1)
{
if (ymove == 1) printf("LEFT DOWN\n");
else if (ymove == 0) printf("LEFT\n");
else if (ymove ==-1) printf("LEFT UP\n");
else printf("UNKNOWN Y\n");
}
else if (xmove == 0)
{
if (ymove == 1) printf("DOWN\n");
/* note that 0,0 can be a timeout, or a direction release. */
else if (ymove == 0)
{
if (game_event->ie_TimeStamp.tv_secs >=
(UWORD)(SysBase->VBlankFrequency)*TIMEOUT_SECONDS)
{
printf("TIMEOUT\n");
timeout=TRUE;
}
else printf("RELEASE\n");
}
else if (ymove ==-1) printf("UP\n");
else printf("UNKNOWN Y\n");
}
else
{
printf("UNKNOWN X ");
if (ymove == 1) printf("unknown action\n");
else if (ymove == 0) printf("unknown action\n");
else if (ymove ==-1) printf("unknown action\n");
else printf("UNKNOWN Y\n");
}
return(timeout);
}
/*-----------------------------------------------------------------------
** send a request to the gameport to read an event.
*/
VOID send_read_request( struct InputEvent *game_event,
struct IOStdReq *game_io_msg)
{
game_io_msg->io_Command = GPD_READEVENT;
game_io_msg->io_Flags = 0;
game_io_msg->io_Data = (APTR)game_event;
game_io_msg->io_Length = sizeof(struct InputEvent);
SendIO(game_io_msg); /* Asynchronous - message will return later */
}
/*-----------------------------------------------------------------------
** simple loop to process gameport events.
*/
VOID processEvents( struct IOStdReq *game_io_msg,
struct MsgPort *game_msg_port)
{
BOOL timeout;
SHORT timeouts;
SHORT button_count;
BOOL not_finished;
struct InputEvent game_event; /* where input event will be stored */
/* From now on, just read input events into the event buffer,
** one at a time. READEVENT waits for the preset conditions.
*/
timeouts = 0;
button_count = 0;
not_finished = TRUE;
while ((timeouts < 6) && (not_finished))
{
/* Send the read request */
send_read_request(&game_event,game_io_msg);
/* Wait for joystick action */
Wait(1L << game_msg_port->mp_SigBit);
while (NULL != GetMsg(game_msg_port))
{
timeout=FALSE;
switch(game_event.ie_Code)
{
case IECODE_LBUTTON:
printf(" FIRE BUTTON PRESSED \n");
break;
case (IECODE_LBUTTON | IECODE_UP_PREFIX):
printf(" FIRE BUTTON RELEASED \n");
if (3 == ++button_count)
not_finished = FALSE;
break;
case IECODE_RBUTTON:
printf(" ALT BUTTON PRESSED \n");
button_count = 0;
break;
case (IECODE_RBUTTON | IECODE_UP_PREFIX):
printf(" ALT BUTTON RELEASED \n");
button_count = 0;
break;
case IECODE_NOBUTTON:
/* Check for change in position */
timeout = check_move(&game_event);
button_count = 0;
break;
default:
break;
}
if (timeout)
timeouts++;
else
timeouts=0;
}
}
}
/*-----------------------------------------------------------------------
** allocate the controller if it is available.
** you allocate the controller by setting its type to something
** other than GPCT_NOCONTROLLER. Before you allocate the thing
** you need to check if anyone else is using it (it is free if
** it is set to GPCT_NOCONTROLLER).
*/
BOOL set_controller_type(BYTE type, struct IOStdReq *game_io_msg)
{
BOOL success = FALSE;
BYTE controller_type = 0;
/* begin critical section
** we need to be sure that between the time we check that the controller
** is available and the time we allocate it, no one else steals it.
*/
Forbid();
game_io_msg->io_Command = GPD_ASKCTYPE; /* inquire current status */
game_io_msg->io_Flags = IOF_QUICK;
game_io_msg->io_Data = (APTR)&controller_type; /* put answer in here */
game_io_msg->io_Length = 1;
DoIO(game_io_msg);
/* No one is using this device unit, let's claim it */
if (controller_type == GPCT_NOCONTROLLER)
{
game_io_msg->io_Command = GPD_SETCTYPE;
game_io_msg->io_Flags = IOF_QUICK;
game_io_msg->io_Data = (APTR)&type;
game_io_msg->io_Length = 1;
DoIO( game_io_msg);
success = TRUE;
}
Permit(); /* critical section end */
return(success);
}
/*-----------------------------------------------------------------------
** tell the gameport when to trigger.
*/
VOID set_trigger_conditions(struct GamePortTrigger *gpt,
struct IOStdReq *game_io_msg)
{
/* trigger on all joystick key transitions */
gpt->gpt_Keys = GPTF_UPKEYS | GPTF_DOWNKEYS;
gpt->gpt_XDelta = JOY_X_DELTA;
gpt->gpt_YDelta = JOY_Y_DELTA;
/* timeout trigger every TIMEOUT_SECONDS second(s) */
gpt->gpt_Timeout = (UWORD)(SysBase->VBlankFrequency) * TIMEOUT_SECONDS;
game_io_msg->io_Command = GPD_SETTRIGGER;
game_io_msg->io_Flags = IOF_QUICK;
game_io_msg->io_Data = (APTR)gpt;
game_io_msg->io_Length = (LONG)sizeof(struct GamePortTrigger);
DoIO(game_io_msg);
}
/*-----------------------------------------------------------------------
** clear the buffer. do this before you begin to be sure you
** start in a known state.
*/
VOID flush_buffer(struct IOStdReq *game_io_msg)
{
game_io_msg->io_Command = CMD_CLEAR;
game_io_msg->io_Flags = IOF_QUICK;
game_io_msg->io_Data = NULL;
game_io_msg->io_Length = 0;
DoIO(game_io_msg);
}
/*-----------------------------------------------------------------------
** free the unit by setting its type back to GPCT_NOCONTROLLER.
*/
VOID free_gp_unit(struct IOStdReq *game_io_msg)
{
BYTE type = GPCT_NOCONTROLLER;
game_io_msg->io_Command = GPD_SETCTYPE;
game_io_msg->io_Flags = IOF_QUICK;
game_io_msg->io_Data = (APTR)&type;
game_io_msg->io_Length = 1;
DoIO(game_io_msg);
}
/*-----------------------------------------------------------------------
** allocate everything and go. On failure, free any resources that
** have been allocated. this program fails quietly-no error messages.
*/
VOID main(int argc,char **argv)
{
struct GamePortTrigger joytrigger;
struct IOStdReq *game_io_msg;
struct MsgPort *game_msg_port;
/* Create port for gameport device communications */
if (game_msg_port = CreatePort("RKM_game_port",0))
{
/* Create message block for device IO */
if (game_io_msg = (struct IOStdReq *)
CreateExtIO(game_msg_port,sizeof(*game_io_msg)))
{
game_io_msg->io_Message.mn_Node.ln_Type = NT_UNKNOWN;
/* Open the right/back (unit 1, number 2) gameport.device unit */
if (!OpenDevice("gameport.device",1,game_io_msg,0))
{
/* Set controller type to joystick */
if (set_controller_type(GPCT_ABSJOYSTICK,game_io_msg))
{
/* Specify the trigger conditions */
set_trigger_conditions(&joytrigger,game_io_msg);
printInstructions();
/* Clear device buffer to start from a known state.
** There might still be events left
*/
flush_buffer(game_io_msg);
processEvents(game_io_msg,game_msg_port);
/* Free gameport unit so other applications can use it ! */
free_gp_unit(game_io_msg);
}
CloseDevice(game_io_msg);
}
DeleteExtIO(game_io_msg);
}
DeletePort(game_msg_port);
}
}
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