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Bit lasered rom figure 3, Wire crc generator figure 4 – Rainbow Electronics DS2417 User Manual

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DS2417

3 of 15

64-bit ROM and ROM Function Control section allow the DS2417 to operate as a 1-Wire device and
follow the 1-Wire protocol detailed in the section "1-Wire Bus System".

HIERARCHICAL STRUCTURE FOR 1-WIRE PROTOCOL Figure 2

DS2417

Command
Level

Available
Commands

Data Fields

Affected

1-Wire Bus

Other
Devices

Bus

Master

DS2417 specific

Function Commands

(see Figure 5)

Write Clock
Read Clock

RTC Counter, Device Control
RTC Counter, Device Control

Read ROM
Match ROM
Search ROM
Skip ROM

64-bit ROM
64-bit ROM
64-bit ROM
N/A

1-Wire ROM Function

Commands (see Figure 7)

64-BIT LASERED ROM Figure 3

MSB

LSB

8-Bit CRC Code

48-Bit Serial Number

8-Bit Family Code (27h)

MSB

LSB MSB

LSB MSB

LSB

1-WIRE CRC GENERATOR Figure 4

R

X

2

X

1

X

0

X

8

X

7

X

6

X

5

X

4

X

3

8TH

STAGE

7TH

STAGE

6TH

STAGE

5TH

STAGE

4TH

STAGE

3RD

STAGE

2ND

STAGE

1ST

STAGE

S

INPUT DATA

Polynomial = X

8

+ X

5

+ X

4

+ 1