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pinapi.c

#include "pinapi.h"
#include <dos.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>

static char pinstring[9];

static int init = 0;

void init_pins() {
    union  REGS  inregs;
    union  REGS  outregs;
            
    inregs.h.ah = 0x83;
    inregs.x.dx = 0x40;
    int86(0xA2, &inregs, &outregs);

    outport(0xff70, inport(0xff70) |  0x0408); // Mode als Ausgang (Mode=1)
    outport(0xff72, inport(0xff72) & ~0x0408); // LED 1 & PIN 7 als Ausgang (Direction=0)

    init = 1;
}

bool getPinStatus(int pin)
{
    byte pinset, bitmask;

    if (!init) {
        init_pins();
    }

    if ( (pin < 0) || (pin > 7) ) { /* false for non-existing pins */
        return 0;
    }

    /* read in the actual status of pin 0 - 7*/
    pinset = inportb(0x600);
    bitmask = 1 << pin;
    return (pinset & bitmask);
}

byte getAllPinStatus()
{
    if (!init) {
        init_pins();
    }

    return inportb(0x600);
}

char* getAllPinStatus_string()
{
    int pinset;
    int i;
    char pin_str[4];
    byte pinstatus;
    char tmp[2];

    pinstring[8] = 0;

    if (!init) {
        init_pins();
    }

    pinstatus = getAllPinStatus();
    sprintf(pin_str, "%d", pinstatus);
    pinset = atoi(pin_str);
    for (i = 7; i >= 0; i--) {
        sprintf(tmp, "%d", div(pinset, (1<<i)));
        pinstring[i] = tmp[0];
        pinset = pinset % (1<<i);
    }

    return pinstring;
}

void setPin(int pin, bool set)
{
    byte pinset;
    unsigned int pio0;
    
    if (!init) {
        init_pins();
    }

    if ( (pin < 0) || (pin > 7) ) { /* false for non-existing pins */
        return;
    }

    pinset = inportb(0x600); /* read the current value */

    switch(set){
        case 0: 
            pinset &= ~(1<<pin);
            outportb(0x600, pinset);
            pio0 = inport(0xff74); /* PIO0 Register aus AM186 lesen */
            pio0 &= ~0x0400;       /* Bit 10 in PIO0 Register ist IO7 */
            if (pinset & 0x80) {
                pio0 |= 0x0400;
            }
            outport(0xff74, pio0);
            break;
        case 1: 
            pinset |=  1<<pin;
            outportb(0x600, pinset);
            pio0 = inport(0xff74); /* PIO0 Register aus AM186 lesen */
            pio0 &= ~0x0400;       /* Bit 10 in PIO0 Register ist IO7 */
            if (pinset & 0x80) {
                pio0 |= 0x0400;
            }
            outport(0xff74, pio0);
            break;
      default: break;
    }
}

void setAllPins(byte set)
{
    byte pinset;
    unsigned int pio0;

    if (!init) {
        init_pins();
    }

    pinset = set;
    outportb(0x600, pinset);
    pio0 = inport(0xff74); /* PIO0 Register aus AM186 lesen */
    pio0 &= ~0x0400;       /* Bit 10 in PIO0 Register ist IO7 */
    if (pinset & 0x80) {
        pio0 |= 0x0400;
    }
    outport(0xff74, pio0);
}

void setAllPins_string(char* setString)
{
    byte pinset = 0;
    int potenz = 0;
    int i;

    if (!init) {
        init_pins();
    }

    if ( (strlen(setString) > 8) || (strlen(setString) == 0) ) {
        return;
    }

    for (i = 0; i < 8; i++, potenz++) {
        pinset += (setString[i] - 48) * (1 << potenz);
    }

    setAllPins(pinset);
}

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