Intel mcs-48 manual 8294

Models: mcs-48

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8294

DATA ENCRYPTION UNIT

Certified by National Bureau of Standards

SO Byte/Sec Data Conversion Rate

64·Blt Data Encryption Using 56· Bit

Key

DMA Interface

3 Interrupt Outputs to Aid In Loading and Unloading Data

DESCRIPTION

7·Blt User Output Port

Single 5V ::t 10% Power Supply

Peripheral to MCS·S6™, MCS·S5™, MC5-S0™ and MCS·48™ Processors

Implements Federal Information Processing Data Encryption Standard

Encrypt and Decrypt Modes Available

The Intell!> 8294 Data Encryption Unit (DEU) is a microprocessor peripheral device designed to encrypt and decrypt 64·bitblocks of data using the algorithm specified in the Federal Information Processing Data Encryption Standard. The DEU operates on 64·bittext words using a 56·bituser·specifledkey to produce 64·bltcipher words. The operation is reversible: if the cipher word Is operated upon, the original text word is produced. The algorithm itself is perma· nently contained in the 8294; however, the 56·blt key is user·defined and may be changed at any time.

The 56·bit key and 64·bltmessage data are transferred to and from the 8294 in 8·bitbytes by way of the system data bus. A DMA interface and three interrupt outputs are available to minimize software overhead associated with data transfer. Also, by using the DMA interface two or more DEUs may be operated In parallel to achieve effective system conversion rates which are virtually any multiple of 80 bytes/second. The 8294 also has a 7·bitTTL compatible output port for user·specified functions.

Because the 8294 implements the NBS encryption algorithm it can be used in a variety of Electronic Funds Transfer applications as well as other electronic banking and data handling applications where data must be encrypted.

 

PIN

 

CONFIGURATION

BLOCK DIAGRAM

 

 

Vee

DATA

 

 

Ne

 

 

BUS

 

 

!lACK

 

 

 

 

 

ORO

 

 

 

SRO

 

 

 

DAV

 

 

 

Ne

 

 

 

P6

Ac

 

 

PS

 

 

P'

SRQ

 

 

P3

DAV

 

 

P2

teMP

01

 

PI

po'p,

02

 

PO

RESET

03

 

VDD

 

SYNC

D4

 

Ne

 

 

OS

 

CCMP

X,

06

 

Ne

07

 

Ne

x,

GND

 

NC

 

 

 

 

+5V -

POWER --

INTERNAL

BUS

OND --

 

9-121

oo230B

Page 436
Image 436
Intel mcs-48 manual 8294