/*  AD.C
 *
 *  Analog Input Routines for the SBC1190 with 8 Channel A/D option
 *
 *  This example can be compiled to an EXE file that polls the A/D convertor
 *  until the conversion is complete or to an EXE file that uses an
 *  interrupt to signal completion of the conversion.
 *
 *  8/3/98
 *  10/15/99     fix editing error that removed convdone reset
 */

#define INTDRIVEN        /* comment this line out for polled conversion */

#include <conio.h>
#include <dos.h>

#define INTCTRLLD       0
#define RANGE5V         0
#define RANGE10V        1
#define UNIPOLAR        0
#define BIPOLAR         1

#ifdef __TURBOC__
#ifndef inpw
#define inpw            inport
#endif
#ifndef outpw
#define outpw           outport
#endif
#ifndef _dos_setvect
#define _dos_setvect    setvect
#endif
#endif

#define ADCTRL               0xFE44          /* write only */
#define ADDATA               0xFE44          /* read only  */
#define ADDATALO             0xFE44          /* read only  */
#define ADDATAHI             0xFE45          /* read only  */

#define PCB          0x0FF00        /*  default base address after reset */
#define EOI          PCB+0x002
#define IMASK        PCB+0x008
#define P2PIN        PCB+0x05A

int advalue;
int convdone;

void far interrupt adinthndlr(void)
{
	advalue = inpw(ADDATA);            /* read the data   */

	convdone = 1;

	outpw(EOI, 0x8000);
}


/*-----------------------------------------------------------------------*     
 *  analogrd(int chan)                                                   *
 *          This function reads analog input in the                      *
 *                                         range set by configadc()      *
 *          given a channel number of 0 to 7                             *
 *  Return value : Integer { -2047 to +2048 } or { 0 to 4095 }           *
 *-----------------------------------------------------------------------*/

unsigned int controlbyte = 0;

int analogrd(int chan)
{
	int value;


	if ((chan<0) || (chan >7))
		return(-999);

	convdone = 0;

	outp(ADDATA, controlbyte | chan);   /* write control word   */
					   /* and start conversion */

	#ifdef INTDRIVEN

	while (!convdone)
		;

        convdone = 0;                   /* reset convdone */
	value = advalue;

	#else  /* POLLED */

	while (!(inp(P2PIN) & 4))        /* wait for signal to rise */
		;

	value = inpw(ADDATA);            /* read the data   */
	#endif

	return(value);
}


/*-----------------------------------------------------------------------*
 *  configadc(int acqmod, int rng, int bip)                              *
 *          This function configures the ADC for mode of acquisition,    *
 *          range, and polarity                                          *
 *          Send a 0 or 1 to the function variables as follows:          *
 *              acqmod = 0 ---> internally controlled acquisition        *
 *              acqmod = 1 ---> externally controlled acquisition        *
 *              RNG    = 0 ---> 5V range                                 *
 *              RNG    = 1 ---> 10V range                                *
 *              BIP    = 0 ---> + RNG range                              *
 *              BIP    = 1 ---> +/- RNG range                            *
 *-----------------------------------------------------------------------*/

void configadc(int acqmod, int rng, int bip)
{
	controlbyte = 0x40;

	if (acqmod)
		controlbyte = controlbyte | 0x20;

	if (rng)
		controlbyte = controlbyte | 0x10;

	if (bip)
		controlbyte = controlbyte | 0x08;
}

void main(void)
{
	int key,n;
	float adcval;

	#ifdef INTDRIVEN
	/* AD conversion-complete interrupt signal is INT3, which translates
	to an interrupt type of 0Fh */
	_dos_setvect(0xF, adinthndlr);
	outp(IMASK, inp(IMASK) & 0x7F); /* unmask INT3 */

	#endif


	configadc(INTCTRLLD, RANGE10V, BIPOLAR); /* internal controlled acq., +/- 10v range */

	printf("Reading 8 channels\n\n");

	printf("Ch0    Ch1    Ch2    Ch3    Ch4    Ch5    Ch6    Ch7\n");


	for(;;)
	{
		for(n=0; n<8; n++)
		{
			adcval = (float)analogrd(n)*10.0/2048.0 +.005;
			printf("%-+6.2f ", adcval);
		}
		printf("\r");
	}
}