DS1922E-F5 MAXIM [Maxim Integrated Products], DS1922E-F5 Datasheet - Page 17

• Manufacturer Part Number: DS1922E-F5
• Description: High-Temperature Logger iButton with 8KB Data-Log Memory
• Manufacturer: MAXIM [Maxim Integrated Products]

The content of the Mission Start Delay Counter register
tells how many minutes must expire from the time a
mission was started until the first measurement of the
mission takes place (SUTA = 0) or until the device
starts testing the temperature for a temperature alarm
(SUTA = 1). The Mission Start Delay is stored as an
unsigned 24-bit integer number. The maximum delay is
16,777,215min, equivalent to 11,650 days or roughly
31yr. If the start delay is nonzero and the SUTA bit is
set to 1, first the delay must expire before the device
starts testing for temperature alarms to begin logging
data.
For a typical mission, the Mission Start Delay is 0. If a
mission is too long for a single DS1922E to store all
readings at the selected sample rate, one can use sev-
eral devices and set the Mission Start Delay for the sec-
ond device to start recording as soon as the memory of
the first device is full, and so on. The RO bit in the
Mission Control register (address 0213h) must be set to
0 to prevent overwriting of collected data once the
data-log memory is full.
Note: During a mission, there is only read access to this register.
Note: There is only read access to this register.
Note: There is only read access to this register.
ADDRESS
ADDRESS
ADDRESS
021Ah
021Bh
021Ch
021Dh
0219h
021Eh
0220h
0221h
0222h
0216h
0217h
0218h
High-Temperature Logger iButton with 8KB
CENT
BIT 7
BIT 7
BIT 7
______________________________________________________________________________________
0
0
0
0
12/24
BIT 6
BIT 6
BIT 6
Mission Start Delay
0
0
10 Years
10 Seconds
10 Minutes
20 Hours
AM/PM
BIT 5
BIT 5
BIT 5
0
10 Date
10 Months
10 Hours
BIT 4
BIT 4
BIT 4
Delay Center Byte
Delay High Byte
Delay Low Byte
Center Byte
High Byte
Low Byte
The Mission Timestamp register indicates the date and
time of the first temperature sample of the mission.
There is only read access to the Mission Timestamp
register.
Depending on settings in the Mission Control register
(address 0213h), the DS1922E logs temperature in 8-bit
or 16-bit format. The Mission Samples Counter together
with the starting address and the logging format (8 or 16
bits) provide the information to identify valid blocks of
data that have been gathered during the current
(MIP = 1) or latest mission (MIP = 0). See the Data-Log
Memory Usage section for an illustration.
The number read from the mission samples counter
indicates how often the DS1922E woke up during a
mission to measure temperature. The number format is
24-bit unsigned integer. The mission samples counter
is reset through the Clear Memory command.
Mission Start Delay Counter Register
BIT 3
BIT 3
BIT 3
Mission Samples Counter Register
Data-Log Memory
Mission Timestamp Register
BIT 2
BIT 2
BIT 2
Mission Progress Indicator
Single Seconds
Single Minutes
Single Months
Single Hours
Single Years
Single Date
Mission Timestamp
BIT 1
BIT 1
BIT 1
BIT 0
BIT 0
BIT 0
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