Chapter 9 Pin Functions

Question 1

are connected to the status output pins on the 8086/8088 microprocessor

Answer 1

Status Inputs (S2, S1, S0)

Question 2

provides internal timing and must be connected to the CLK output pin of the 8284A clock generator.

Answer 2

Clock Input (CLK)

Question 3

is used to demultiplex the address/data bus.

Answer 3

Address Latch Enable (ALE)

Question 4

controls the bidirectional data bus buffers in the system

Answer 4

Data Bus Enable (DEN)

Question 5

is output by the 8288 to control the direction of the bidirectional data bus buffers.

Answer 5

Data Transmit/Receive (DT/R)

Question 6

causes the 8288 to enable the memory control signals.

Answer 6

Address Enable (AEN)

Question 7

enables the command output pins on the 8288

Answer 7

Control Enable (CEN)

Question 8

selects either the I/O bus mode or system bus mode operation.

Answer 8

I/O bus mode (IOB)

Question 9

is a command output used to provide I/O with an advanced I/O write control signal.

Answer 9

Advanced Input/Output Write Command (AIOWC)

Question 10

provides I/O with its read control signal.

Answer 10

IORC

Question 11

provides I/O with its main write signal.

Answer 11

IOWC

Question 12

provides memory with an early
or advanced write signal.

Answer 12

Advanced Memory Write (AMWT)

Question 13

provides memory with its normal write control signal.

Answer 13

MWTC

Question 14

provides memory with a read control signal

Answer 14

MRDC

Question 15

acknowledges an interrupt request
input applied to the INTR pin

Answer 15

INTA

Question 16

selects cascade operation for an interrupt controller if IOB is grounded, and enables the I/O bus transceivers if IOB is tied high.

Answer 16

Master Cascade/Peripheral Data (MCE/PDEN)