The Intel 8288 is a bus controller designed for Intel 8086/8087/8088/8089. The chip is supplied in 20-pin DIP package. The 8086 (and 8088) operate in maximum mode, so they are configured primarily for multiprocessor operation or for working with coprocessors. Necessary control signals are generated by the 8288. It was used in the IBM PC, XT and its clones.[1]IBM PC AT used its successor Intel 82288.
Pin assignment and function for the control lines
Name
Pin
Input (I), Output (O)
Function
VCC
20
Input power (+5 V)
GND
10
Ground (0 V)
S0, S1, S2
19, 3, 18
I
Status input
CLK
2
I
Clock
AEN
6
I
Address Enable
CEN
15
I
Command Enable
IOB
1
I
Input/Output Bus Mode
MRDC
7
O
Memory ReadCommand
MWTC
9
O
Memory Write Command
AMWC
8
O
Advanced Memory Write Command
IORC
13
O
I/ORead Command
IOWC
11
O
I/OWrite Command
AIOWC
12
O
Advanced I/OWrite Command
INTA
14
O
Interrupt Acknowledge
DT/R
4
O
Data Transmit/Receive
DEN
16
O
Data Enable
MCE/PDEN
17
O
MCE (if IOB is LOW), PDEN (if IOB is HIGH)
ALE
5
O
Address Latch Enable
Variants
Both Intel 8288 and I8288 (industrial grade) version were available for US$14.30 and $33.75 in quantities of 100 respectively.[2][3] The available 82C88 CMOS version was outsourced to Oki Electronic Industry Co., Ltd.[4] The package version of Intel 82C88 branded in 20-pin PLCC of sampling at fourth quarter of 1985.[5]
