Datasheet

40Maxim Integrated
DS2465
DeepCover Secure Authenticator with
SHA-256 Coprocessor and 1-Wire Master Function
ABRIDGED DATA SHEET
I
2
C Communication Examples (continued)
Case B: 1-Wire Idle (1WB = 0), Busy Polling Until the 1-Wire Command is Completed
S A A A
PSr
AD,0
AD,1
1WSB A
A\
<byte>
A
<byte>A <byte>
60h
Repeat until the
1WB bit has
changed to 0.
When 1WB has changed from 1 to 0, the 1-Wire Master Status register holds the valid result of the 1-Wire Single
Bit command.
Case C: 1-Wire Busy (1WB = 1)
S A A PAD,0 1WSB A\60h
The master should stop and restart as soon as the DS2465 does not acknowledge the command code.
1-Wire Write Byte, e.g., to Send a Command Code to the 1-Wire Line
Case A: 1-Wire idle (1WB = 0), No Busy Polling
S A A A PAD,0 1WWB (Idle)A60h 33h
33h is the valid 1-Wire ROM function command for Read ROM. The idle time is needed for the 1-Wire function to
complete. There is no data read back from the 1-Wire line with this command.
Case B: 1-Wire Idle (1WB = 0), Busy Polling Until the 1-Wire Command is Completed.
S A A AAD,0 1WWB A60h 33h
PSr AD,1 A\A <byte>A <byte>
Repeat until the
1WB bit has
changed to 0.
When 1WB has changed from 1 to 0, the 1-Wire Write Byte command is completed.
Case C: 1-Wire Busy (1WB = 1)
S A AAD,0 1WWB A\60h P
The master should stop and restart as soon as the DS2465 does not acknowledge the command code.
1-Wire Read Byte, e.g., to Read a Byte from the 1-Wire Line
Case A: 1-Wire Idle (1WB = 0), No Busy Polling, Set read address before Idle Time
S A A A
P
PSr
S
AD,0 AAD,0
AD,1
1WRB
(Idle)
A
A\A <byte>
60h 62h
The read address is set to the 1-Wire Read Data register while the 1-Wire Read Byte command is still in progress.
Then, after the 1-Wire function is completed, the device is accessed to read the data byte that was obtained from
the 1-Wire line.