M34C00

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Figure 10. Reading the Protection Register

SDA

AI03719B

NoACK

Data Out

FFh

ACK

Device Select

Code

RW

SDA

NoACK

Data Out

FFh

NoACK

Device Select

Code

RW

If the Protection Register has been set:

If the Protection Register has not yet been set:

Reading the Protection Register

To determine whether the Write-protection feature

has been activated, it is possible to read the

Protection Register, as shown in Figure 10.

– If the Protection Register has not been set, the

device acknowledges the read sequence

– If the Protection Register has been set, the

device deselects itself after it has received the

device select code. Consequently, each part of

the sequence is not acknowledged.

Figure 9. Setting the Protection Register

SDA

AI03718

ACK

Byte Address

Don't Care

ACK

Data In

Don't Care

ACK

Device Select

Code

RW

SDA

NoACK

Byte Address

Don't Care

NoACK

Data In

Don't Care

NoACK

Device Select

Code

RW

If the Protection Register has already been set:

If the Protection Register has not yet been set: