🚀 go-pugleaf

	Hello everyone,
	I have to write an TSR interupt handler for one of my project in
school. I can keep the program TSR and function somewhat "OK". But I
having problem releasing from memory.....
	If any expert programmer out there have any clue or suggestion to
release a C TSR program please post or e-mail me...
	Below is a sample program taking from the example to BC++ 2.0
Would you please help me how write the release() procedure or give me a
hint on how this can be accomplished.
				Many, Many Thanks,

#include <dos.h>
/* The clock tick interrupt */
#define INTR 0x1C
/* Screen attribute (blue on grey) */
#define ATTR 0x9700
#define PPI_BASE        0x380            /* 8255 base address         */
#define PORTA 		0x380            /* 8255 port A address       */
#define PORTB 		0x381            /* 8255 port B address       */
#define PORTC 		0x382            /* 8255 port C address       */
#define CONTROL_8255 	0x383	         /* 8255 control word address */
#define SETUP_8255	0x082            /* 8255 control word data    */

/* reduce heaplength and stacklength
to make a smaller program in memory */
extern unsigned _heaplen = 1024;
extern unsigned _stklen  = 512;

void interrupt ( *oldhandler)(void);

void interrupt handler(void)
{
	unsigned int (far *screen)[80];
	static int count;
	int VOLTAGE_u;   /* 8 bit voltage reading from the ADC0808 */

	/* For a color screen the video memory
	   is at B800:0000.  For a monochrome
	   system use B000:000 */
	screen = MK_FP(0xB800,0);

	/* increase the counter and keep it
	   within 0 to 9 */
	count++;
	count %= 10;

	/* put the number on the screen */
	screen[0][79] = count + '0' + ATTR;


	/* Read in the conversion data from port A */
	VOLTAGE_u = inportb(PORTA);

	if (VOLTAGE_u==0)
		{ setvect(INTR, oldhandler);
		  release(); <---------------- this is what i have
				prblem with.
		}
}

int main(void)
{

	/* get the address of the current clock
	   tick interrupt */
	oldhandler = getvect(INTR);

	/* install the new interrupt handler */
	setvect(INTR, handler);

	/* _psp is the starting address of the
	   program in memory.  The top of the stack
	   is the end of the program.  Using _SS and
	   _SP together we can get the end of the
	   stack.  You may want to allow a bit of
	   saftey space to insure that enough room
	   is being allocated ie:
	   (_SS + ((_SP + safety space)/16) - _psp)
	*/
	keep(0, (_SS + (_SP/16) - _psp));
	return 0;
}