hbc56_ramrom_io.pld

Name hbc56_ramrom_io;
Partno hbc5602;
Revision 01;
Date 8/5/2022;
Designer Troy Schrapel;
Company Troy Schrapel;
Location Australia;
Assembly None;
Device g16v8;

/*
 * Input pins
 */
Pin 1 = !io;
Pin 2 = !r;
Pin 3 = a15;
Pin 4 = !b0;
Pin 5 = a3;
Pin 6 = a4;
Pin 7 = a5;
Pin 8 = a6;
Pin 9 = a7;
Pin 11 = clkin;

/*
 * Output pins
 */
Pin 15 = !cw;
Pin 16 = a15b;
Pin 17 = !bre;
Pin 18 = !b1e;
Pin 19 = !b0e;

/*
 * Common logic
 */
bankreg = io & !a7 & !a6 & !a5 & !a4 & a3;  /*  $08  */

bank1en = !b0;

w = !r;
mem = !io;

/*
 * Output logic
 */
cw = clkin & w;
a15b = !a15;
bre = w & bankreg;
b1e = mem & bank1en;
b0e = mem & !bank1en;