Module NEPTUNE1

Declarations
"X68000 side pins
RW pin 85;
UDS pin 86;
LDS pin 87;
AS pin 89;
FC1,FC0 pin 90,91;
DTACK pin 82;
IREQ pin 80;
IACK pin 79;
EXRESET pin 81;
AB1..AB9 pin 37,36,35,34,33,32,30,29,28;
AB10..AB23 pin 8,7,6,4,3,2,1,99,97,96,95,94,93,92;
DB0..DB7 pin 25,24,23,22,20,19,18,17;
DB8..DB15 pin 16,15,14,13,12,11,10,9;

"RTL8019A side pins
IOR pin 55;
IOW pin 54;
"AEN pin;
IOCHRDY pin 52;
INT pin 78;
SA0..SA9 pin 67,66,65,64,63,61,60,59,58,56;
SD0..SD7 pin 39,40,41,42,43,46,49,50;
SD8..SD15 pin 68,70,71,72,73,74,76,77;
RESETDRV pin 53;

CS node;
DIR node;
IVS node;
IDTACK node;
DG node;
SEL node;
Equations
"Address=0xECE000 or 0xECE400
CS = !(([AB23..AB10]==[1,1,1,0,1,1,0,0,1,1,1,0,0,0]) & ([FC1,FC0]==[0,1]));
SEL =!CS & !AS & !(RW & UDS & LDS );
IVS=IACK;
IDTACK=!IACK;
DIR=!RW;
DG=!(SEL # IDTACK);

IREQ=0;
IREQ.oe=INT;

"AEN=0;

IOR=!(RW & SEL);
IOW=!(!RW & SEL);

DTACK=0;
DTACK.oe=IDTACK # (SEL & IOCHRDY);

[DB7..DB0]=(!IVS & [1,1,1,1,1,0,0,1]) # (IVS & [SD15..SD8]);
[DB15..DB8]=[SD7..SD0];
[DB15..DB0].oe = !DG & !DIR;
[SD7..SD0]=[DB15..DB8];
[SD15..SD8]=[DB7..DB0];
[SD15..SD0].oe = !DG & DIR;

[SA9..SA0]=[1,AB9..AB1];

RESETDRV = !EXRESET;
End