MC10H165

2–263

MOTOROLA

MECL Data

DL122 — Rev 6

APPLICATION INFORMATION

A typical application of the MC10H165 is the decoding

of system status on a priority basis. A 64–line priority

encoder is shown in the figure below. System status lines

are connected to this encoder such that, when a given

condition exists, the respective input will be at a logic high

level. This scheme will select the one of 64 different

system conditions, as represented at the encoder inputs,

which has priority in determining the next system

operation to be performed. The binary code showing the

address of the highest priority input present will appear at

the encoder outputs to control other system logic

functions.

Q2

Six bit output

word yielding

number of

highest priority

channel present

at input

ZZZ

MC10H164

MC10H164

MC10H164

X0

X7

. . . . . . .

A B C

C

D0

D7

Q0

Q1

Q2

LSB

MSB

C

D0

D7

Q0

Q1

Q2

Q3

C

D0

D7

C

D0

D7

C

D0

D7

C

D0

D7

C

D0

D7

C

D0

D7

C

D0

D7

Q0

Q1

Q2

Q3

Q0

Q1

Q2

Q3

Q0

Q1

Q2

Q3

Q0

Q1

Q2

Q3

Q0

Q1

Q2

Q3

Q0

Q1

Q2

Q3

Q0

Q3

1/2 MC10H101

System

Clock

Highest

Priority

Input

Lowest

Priority

Input

64–LINE PRIORITY ENCODER

X0

X7

. . . . . . .

A B C

X0

X7

. . . . . . .

A B C

Q1