1024-Bit, 1-Wire EEPROM

10

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BUS MASTER Tx MEMORY

FUNCTION COMMAND

BUS MASTER Tx

TA1 (T[7:0]), TA2 (T[15:8])

BUS MASTER Rx

TA1 (T[7:0]), TA2 (T[15:8]),

AND E/S BYTE

BUS MASTER Rx

DATA BYTE FROM

SCRATCHPAD

MASTER Tx DATA BYTE

TO SCRATCHPAD

APPLIES ONLY

IF THE MEMORY

AREA IS NOT

PROTECTED.

IF WRITE PROTECTED,

THE DS2431 COPIES

THE DATE BYTE FROM

THE TARGET ADDRESS

INTO THE SCRATCHPAD.

IF IN EPROM MODE,

THE DS2431 LOADS

THE BITWISE LOGICAL

AND OF THE TRANSMITTED

BYTE AND THE DATA

BYTE FROM THE TARGETED

ADDRESS INTO THE

SCRATCHPAD.

BUS MASTER

Rx "1"s

DS2431

INCREMENTS

E[2:0]

PF = 0

DS2431

SETS PF = 1

CLEARS AA = 0

SETS E[2:0] = T[2:0]

0Fh

WRITE SCRATCHPAD?

N

Y

N

Y

N

Y

Y

Y

N

N

MASTER Tx RESET?

E[2:0] = 7?

T[2:0] = 0?

MASTER Tx RESET?

DS2431 SETS

SCRATCHPAD

BYTE COUNTER = T[2:0]

AAh

READ SCRATCHPAD?

N

Y

DS2431 Tx CRC-16 OF

COMMAND, ADDRESS,

AND DATA BYTES AS THEY

WERE SENT BY THE BUS

MASTER

BUS MASTER

Rx "1"s

Y

N

MASTER Tx RESET?

BUS MASTER Rx CRC-16

OF COMMAND, ADDRESS,

E/S BYTE, AND DATA BYTES

AS SENT BY THE DS2431

Y

N

MASTER Tx RESET?

Y

BYTE COUNTER

= E[2:0]?

FROM ROM FUNCTIONS

FLOWCHART (FIGURE 9)

TO ROM FUNCTIONS

FLOWCHART (FIGURE 9)

DS2431

INCREMENTS

BYTE COUNTER

N

TO FIGURE 7b

FROM FIGURE 7b

Figure 7a. Memory Function Flowchart