68k Bootstrap

/*
Source for 68k bin:

M68000
    DL 0
    DL 8

    MOVE.B  #$FF, D1

LOOP:
    MOVE.L  #$FF, D0

LOOPW1:
    SUBQ    #1, D0
    BNE LOOPW1

    MOVE.B  D1, $010000
    NOT D1
    BRA LOOP

*/
#include <stdint.h>

uint8_t data[0x20] = {
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x08,
0x12, 0x3c, 0x00, 0xff,
0x20, 0x3c, 0x00, 0x00,
0x00, 0xff, 0x53, 0x40,
0x66, 0xfc, 0x13, 0xc1,
0x00, 0x01, 0x00, 0x00,
0x46, 0x41, 0x60, 0xec
};

void bus_highz()
{
    int _c;
    for (_c = 2; _c <= 9; _c++)
      pinMode(_c, INPUT);
}

void bus_out(uint8_t data)
{
    int _c;
    for (_c = 2; _c <= 9; _c++)
      pinMode(_c, OUTPUT);
    for (_c = 0; _c < 8; _c++)
      digitalWrite(2 + _c, data & (1 << _c));
}

uint8_t get_addr()
{
    uint8_t _c;
    uint8_t _b = 0;
    for (_c = 0; _c < 5; _c++)
      _b |= (digitalRead(A0 + _c) ? 1 : 0) << _c;
      _b |= (digitalRead(10) ? 1 : 0) ;
  return _b;
}

void do_read(){
  uint8_t addr = get_addr();
      Serial.println(addr);
  bus_out(data[addr]);
  digitalWrite(12, LOW);
}

void setup() {
    int _c;
    Serial.begin(115200);
    bus_highz();
    for (_c = 0; _c < 5; _c++)
      pinMode(A0 + _c, INPUT);
    pinMode(A5, INPUT);
    pinMode(10, INPUT);
    pinMode(11, INPUT);
    pinMode(12, OUTPUT);
    pinMode(13, OUTPUT);
    digitalWrite(13, LOW);
    digitalWrite(12, LOW);
    digitalWrite(13, LOW);
}
void loop() {
  if (digitalRead(A5) || !digitalRead(11)) {//IF READ & NOT *RAMCS
      bus_highz();
      digitalWrite(12, LOW);

  } else {
      digitalWrite(12, LOW);//Deassert SETARDUDTACK
      do_read();
      digitalWrite(12, HIGH);//Assert SETARDUDTACK
  }
}