DS1923 Maxim, DS1923 Datasheet - Page 33

• 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

Figure 9c. Memory/Control Function Flowchart (continued)
Hygrochron Temperature/Humidity Logger
______________________________________________________________________________________
FROM FIGURE 9b
TO FIGURE 9b
N
Y
N
N
iButton with 8KB Data-Log Memory
DS1923 INITIATES MISSION
START DELAY PROCESS
64 BITS [PASSWORD]
MASTER Tx RESET?
FFh DUMMY BYTE
START MISSION
MEMCLR = 1?
DS1923 SETS
MEMCLR = 0
PASSWORD
ACCEPTED?
PROGRESS?
MASTER Tx
MASTER Tx
MISSION IN
[WITH PW]
MIP = 1,
CCh
Y
Y
N
Y
Y
N
Y
MISSION TIMESTAMP REGISTER
DS1923 WAITS FOR 1 MINUTE
DS1923 COPIES RTC DATA TO
TEMPERATURE CONVERSION
AND LOGS FIRST SAMPLE
DS1923 STARTS LOGGING
DS1923 PERFORMS 8-BIT
START DELAY COUNTER
DS1923 SETS WFTA = 1
DS1923 SETS WFTA = 0
TAKING FIRST SAMPLE
DS1923 DECREMENTS
DS1923 WAITS ONE
DS1923 WAITS ONE
END OF PROCESS
DELAY PROCESS
SAMPLE PERIOD
SAMPLE PERIOD
MISSION START
COUNTER = 0?
TEMPERATURE
START DELAY
SUTA = 1?
MIP = 0?
ALARM?
N
Y
N
Y
Y
N
N
THE MISSION
SAMPLES COUNTER
DOES NOT
INCREMENT
IF SUTA = 1,
THIS IS THE
SECOND SAMPLE.
64 BITS [PASSWORD]
MASTER Tx RESET?
FFh DUMMY BYTE
STOP MISSION
DS1923 SETS
ACCEPTED?
PROGRESS?
MASTER Tx
MASTER Tx
PASSWORD
MISSION IN
[WITH PW]
WFTA = 0
MIP = 0,
33h
Y
Y
Y
Y
N
N
N
N
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