Intel 80386

LOCAL BUS CONTROL PAL DESCRIPTIONS
module
title
'80386 Local Bus Controller - pal 2
Intel Corp'
BC386P2
device 'P16R8'i "use a 16R8 B-speed PAL for 16MHz 386
" Constants:
ON
OFF
H
L
x
c
1;
0;
1;
0;
.x. ;
.c. ;
" ABEL 'don't care' symbol
" ABEL 'clocking input' symbol
" state definitions for LOCALSTATE (local cycle state):
"waiting for next bus cycle
WAITING
SAMPLECS
CMDDELAY
IO
AblOl;
AblOO;
AbOOO;
Ab010;
AbllO;
AbOll;
Ablll;
Ab001;
"CLK2 before ALE falls and CS is sampled
"delay before CMD active
"IO CMD active
"IO CMD inactive
"lWS CMD active
"data bus float delay
ENDIO
MEMORY
FLOAT
NOTLOCAL
"OWS cycle or bus cycle not to the local bus
II Pin names:
CLK
MIO
DC
WR
LO
Ll
L2
CSOWS
CLK2
OE
MRDC
MWTC
IORC
IOWC
INTA
pin
2 ;
pin
3 ;
pin 4 ;
pin
5;
pin 6;
pin
7;
pin 8 ;
pin
9 ;
pin
1;
pin
11;
pin
19;
pin 18;
pin
17 ;
pin 16;
pin
15;
"
Input pins
"
82384 CLK
"
80386 M/IO#
"
80386 D/C#
"
80386 W/R#
"
local cycle
state (from PAL 1)
"
local cycle
state (from PAL 1)
"
local cycle state (from PAL 1)
" chip-select for 0 wait-state (piped) devices
" Clock pin - 82384
CLK2
" output Enable pin
"
output pins
" Memory Read
Control signal
"
Memory Write Control signal
"
I/O
Read Control
signal
"
I/O
write Control signal
"
Interrupt Acknowledge Control signal
ALE
pin
14;
"
Address Latch Enable Control
signal
DEN pin
13;
"
Data Transceiver Enable Control signal
RDY pin 12;
"
READY signal
LOCALSTATE
[L2,
Ll,
LO] ;
"
local
cycle state
" Macros:
ifMEMORYREAD macro
{ ( MIO & !WR)
}; It true
for
memory
data or code read
ifMEMORYWRITE
macro
{ ( MIO &
DC & WR)
};
II true
for memory data write
ifIOREAD macro
{ (!MIO & DC & !WR) }; " true for I/O data read
ifIOWRITE macro
{ (!MIO & DC & WR) }; " true for I/O data write
ifINTACK macro
{ (!MIO & !DC & !WR) }; " true for interrupt acknowledge cycle
Figure A-2. PAL-2 State Listings
A-9