DS1923 Maxim, DS1923 Datasheet - Page 32

• Manufacturer Part Number: DS1923
• Description: The DS1923 temperature/humidity logger iButton® is a rugged, self-sufficient system that measures temperature and/or humidity and records the result in a protected memory section
• Manufacturer: Maxim

Hygrochron Temperature/Humidity Logger
iButton with 8KB Data-Log Memory
Figure 9b. Memory/Control Function Flowchart (continued)
32
FROM FIGURE 9a
TO FIGURE 9a
______________________________________________________________________________________
DECISION MADE
DECISION MADE
BY MASTER
BY DS1923
MASTER Tx RESET
Y
N
MEMORY ADDRESS = [T15:T0]
MASTER Rx DATA BYTE FROM
(1ST PASS); CRC-16 OF DATA
COMMAND, ADDRESS, DATA
TA1 [T7:T0], TA2 [T15:T8]
(SUBSEQUENT PASSES)
MASTER Rx CRC-16 OF
READ MEMORY [WITH
64 BITS [PASSWORD]
MEMORY ADDRESS
MASTER Tx RESET?
MASTER Tx RESET?
END OF MEMORY?
END OF PAGE?
PW] AND CRC
DS1923 SETS
ACCEPTED?
MASTER Tx
MASTER Tx
PASSWORD
CRC OK?
Y
69h
Y
Y
N
Y
Y
Y
N
N
N
N
N
MASTER Rx "1"s
INCREMENTS
ADDRESS
COUNTER
DS1923
N
MISSION SAMPLES COUNTER,
MISSION TIMESTAMP,
64 BITS [PASSWORD]
MASTER Tx RESET?
FFh DUMMY BYTE
CLEAR MEMORY
DS1923 CLEARS
ALARM FLAGS
DS1923 SETS
MEMCLR = 1
ACCEPTED?
PROGRESS?
MASTER Tx
MASTER Tx
PASSWORD
MISSION IN
[WITH PW]
96h
Y
Y
N
Y
N
N
Y
N
TEMPERATURE CONVERSION
DS1923 COPIES RESULT TO
DS1923 COPIES RESULT TO
HUMIDITY CONVERSION
FORCED CONVERSION?
DS1923 PERFORMS A
DS1923 PERFORMS A
MASTER Tx RESET?
ADDRESS 020C/Dh
FFh DUMMY BYTE
ADDRESS 020E/Fh
PROGRESS?
MASTER Tx
MISSION IN
55h
Y
N
Y
N
Y
FROM FIGURE 9c
TO FIGURE 9c