Intel 80386

LOCAL BUS INTERFACE
Table 3-1. Summary of 80386 Signal Pins
Input
Output
Signal
Name Signal Function
Active
Input! Synch or
High Impedance
State Output Asynch
During HLDA?
to CLK2
CLK2 Clock -
I
-
-
DO-D31 Data Bus
High
I/O
8
Yes
BEO#-BE3# Byte Enables Low
0
-
Yes
A2-A31 Address Bus
High
0
-
Yes
W/R#
Write-Read Indication High
0
-
Yes
D/C#
Data-Control Indication
High
0
-
Yes
M/IO# Memory-I/O Indication High 0
-
Yes
LOCK# Bus Lock Indication
Low
0
-
Yes
AD8# Address 8tatus
Low
0
-
Yes
NA# Next Address Request
Low
I 8
-
B816# Bus 8ize 16
Low I
8
-
READY# Transfer Acknowledge
Low
I 8
-
HOLD Bus Hold Request
High
I 8
-
HLDA Bus Hold Acknowledge
High
0
-
No
PEREQ Coprocessor Request High
I A -
BU8Y# Coprocessor Busy
Low
I A -
ERROR# Coprocessor Error
Low
I A
-
INTR Maskable Interrupt Request
High
I A
-
NMI Non-Maskable Intrpt Request
High
I A
-
RE8ET Reset
High
I 8
-
3-3