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 * 4play.c

#include    <exec/types.h>
#include    <libraries/dos.h>

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

#include    <clib/exec_protos.h>

UBYTE portdata;
UBYTE *portptr = &portdata;

UBYTE firedata;
UBYTE *fireptr = &firedata;

extern int getport(void);
extern void read34(void);
extern void freeport(void);

 * Lattice control-c stop...
int CXBRK(void) { return(0); }      /* Disable Lattice CTRL/C handling */
int chkabort(void) { return(0); }   /* really */

void Quit(char whytext[], LONG return_code)
    if(return_code==0) freeport();  /* Assembly routine to
                                       de-allocate parallel port */


    exit(return_code);              /* returning non-zero
                                       terminates the program */

void main(void)
    BOOL done=FALSE;
    UBYTE error;

    /* getport() is an assembly routine that allocates the parallel port
     * and makes all the lines we're interested in "read" lines.
    if(error=getport()) Quit("Parallel port in use",25);
    /* WARNING:
     * This example continuously reads the ports and checks for CTRL_C,
     * thereby eating a lot of CPU time.  Actual applications that expect
     * to be even more system friendly might want to set up some interrupts
     * on the fire button lines, such that the game can read the ports less
     * often, but never miss a "fire" press.

        read34();       /* read34() is the assembly routine that copies the
                         * relavent data from the port into our variables.

        /* We'll just print the raw bytes from the read, and leave it as an
         * exercise for the reader to mask out the relevant bits.
         * (Check the pinouts to find which bits the switches appear at.)
        printf("portdata = %u, firedata = %u\n",portdata,firedata);

        /* Check CTRL_C */
        if(SetSignal(0L,0L) & SIGBREAKF_CTRL_C) /* Hit since last check? */
            SetSignal(0L,SIGBREAKF_CTRL_C); /* Clear old status */
    Quit("Ctrl-C was pressed.",0);

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