DS1923-F5#W Maxim Integrated Products, DS1923-F5#W Datasheet - Page 25

• Manufacturer Part Number: DS1923-F5#W
• Description: Board Mount Temperature Sensors Hygrochron Temp/Hum Logger w/8KB DataLog
• Manufacturer: Maxim Integrated Products

Specifications of DS1923-F5#W

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Before enabling password checking, passwords for
read-only access as well as for full access
(read/write/control) must be written to the password
registers. Setting up a password or enabling/dis-
abling the password checking is done in the same
way as writing data to a memory location; only the
address is different. Since they are located in the
same memory page, both passwords can be rede-
fined at the same time.
The Read Access Password must be transmitted exact-
ly in the sequence RP0, RP1…RP62, RP63. This pass-
word only applies to the Read Memory with CRC
command. The DS1923 delivers the requested data
only if the password transmitted by the master was cor-
rect or if password checking is not enabled.
Note: There is only write access to this register. Attempting to read the password reports all zeros. The password cannot be
changed while a mission is in progress.
Note: There is only write access to this register. Attempting to read the password reports all zeros. The password cannot be
changed while a mission is in progress.
ADDRESS
ADDRESS
0228h
0229h
022Eh
022Fh
0230h
0231h
0236h
0237h
…
…
Hygrochron Temperature/Humidity Logger
BIT 7
BIT 7
RP15
RP55
RP63
FP15
FP55
FP63
RP7
FP7
______________________________________________________________________________________
BIT 6
RP14
RP54
RP62
BIT 6
FP14
FP54
FP62
RP6
FP6
iButton with 8KB Data-Log Memory
BIT 5
RP13
RP53
RP61
BIT 5
FP13
FP53
FP61
RP5
FP5
BIT 4
RP12
RP52
RP60
BIT 4
FP12
FP52
FP60
RP4
FP4
The Full Access Password must be transmitted exactly
in the sequence FP0, FP1…FP62, FP63. It affects the
commands Read Memory with CRC, Copy Scratchpad,
Clear Memory, Start Mission, and Stop Mission. The
DS1923 executes the command only if the password
transmitted by the master was correct or if password
checking is not enabled.
Due to the special behavior of the write-access logic,
the Password Control register and both passwords
must be written at the same time. When setting up new
passwords, always verify (read back) the scratchpad
before sending the Copy Scratchpad command. After a
new password is successfully copied from the scratch-
pad to its memory location, erase the scratchpad by fill-
ing it with new data (Write Scratchpad command).
Otherwise, a copy of the passwords remains in the
scratchpad for public read access.
…
…
Read-Access Password Register Bitmap
Full-Access Password Register Bitmap
BIT 3
RP11
RP51
RP59
BIT 3
FP11
FP51
FP59
RP3
FP3
BIT 2
RP10
RP50
RP58
BIT 2
FP10
FP50
FP58
RP2
FP2
BIT 1
RP49
RP57
BIT 1
FP49
FP57
RP1
RP9
FP1
FP9
BIT 0
RP48
RP56
FP48
FP56
BIT 0
RP0
RP8
FP0
FP8
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