DS2423

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MEMORY FUNCTION EXAMPLE

Read page 14 and counts of Input A. Rewrite page 14 with 32 bytes. Read Memory + Counter, Write

Scratchpad, Copy Scratchpad.

MASTER MODE

DATA (LSB FIRST)

COMMENTS

TX

Reset

Reset pulse (480-960 µs)

RX

Presence

Presence pulse

TX

CCh

Issue “skip ROM” command

TX

A5h

Issue “read memory + counter” command

TX

C0h

TA1, beginning offset=C0h

TX

01h

TA2, address=01C0h

RX

<32 data bytes>

Read 32 bytes of data

RX

<4 data bytes>

Read Counts of Input A

RX

<4 data bytes>

Read 32 Zero Bits

RX

<2 data bytes>

Read (inverted) CRC16

TX

Reset

Reset pulse

RX

Presence

Presence pulse

TX

CCh

Issue “skip ROM” command

TX

0Fh

Issue “write scratchpad” command

TX

C0h

TA1, beginning offset=C0h

TX

01h

TA2, address=01C0h

TX

<32 data bytes>

Read 32 bytes of data to scratchpad

RX

<2 data bytes>

Read (inverted) CRC16

TX

Reset

Reset pulse

RX

Presence

Presence pulse

TX

CCh

Issue “skip ROM” command

TX

5Ah

Issue “copy scratchpad” command

TX

C0h

TX

01h

TX

1Fh

TA1

TA2

AUTHORIZATION CODE

E/S

RX

<1 data byte>

Read Copy Scratchpad response

TX

Reset

Reset pulse

RX

Presence

Presence pulse, done