CAT34C02

http://onsemi.com

9

Table 9. SWP COMMANDS

WP

PSWP RSWP

X

1

XX

No

GND

0X

0

Yes

X

Yes

X

Yes

Yes

0X

0

Yes

X

Yes

X

No

No

X0

X

1

Yes

X

GND GND

1

X

001

X

No

X

GND GND

0

1

001

X

No

GND GND GND

0

0

0

0

1

0

Yes

X

Yes

X

Yes

Yes

GND GND

0

0

0

0

1

0

Yes

X

Yes

X

No

No

X

GND GND

0

0

0

0

1

1

Yes

X

GND

1

X

011

X

No

GND GND

0

X

0

1

1

0

Yes

X

Yes

X

Yes

Yes

GND

0

X

0

1

1

0

Yes

X

Yes

X

No

No

X

GND

0

X

0

1

1

1

Yes

Set

RSWP

Clear

RSWP

0110

Slave Address

Set

PSWP

Action

Control Pin Levels

Flag State

ACK

?

Write

Cycle

ACK

?

ACK

?

Address

Byte

Data

Byte

(Note 12)

(Note 13)

13.1 stands for ‘Set’, 0 stands for ‘Not Set’, X stands for ‘don’t care’.

BYTE

ADDRESS

SLAVE

ADDRESS

S

A

C

K

A

C

K

DATA

S

T

O

P

P

BUS ACTIVITY:

MASTER

SDA LINE

S

T

A

R

T

X = Don’t Care

X

N

O

A

C

K

or

A

C

K

Figure 14. Software Write Protect (Write)

XX X X X X X X XX XX X X X

SLAVE

ADDRESS

S

N

O

A

C

K

or

A

C

K

S

T

O

P

P

BUS ACTIVITY:

MASTER

SDA LINE

S

T

A

R

T

Figure 15. Software Write Protect (Read)