DS1921G-F5N MAXIM [Maxim Integrated Products], DS1921G-F5N Datasheet - Page 36

• Manufacturer Part Number: DS1921G-F5N
• Description: Thermochron iButton
• Manufacturer: MAXIM [Maxim Integrated Products]

Thermochron iButton
Assumption: The previous mission has ended. To end
an ongoing mission write the MIP bit in the Status regis-
ter to 0.
The preparation of a DS1921G for a mission including
the start of the mission requires up to four steps:
36
Read Memory with CRC (Success)
The “32 bytes” are either valid page data or 00h bytes when reading reserved pages 20 through 63 or 68
through 127 or pages 192 and higher (beyond data-log memory).
Read Memory with CRC (Invalid Address)
The “32 bytes” are all 00h.
Clear Memory
To verify success, read the Status register at address 0214h. If MEMCLR is 1, the command was executed
successfully.
Convert Temperature
To read the result and to verify success, read the addresses 0211h (result) and the Device Samples Counter
at address 021Dh to 021Fh. If the count has incremented, the command was executed successfully.
RST
RST
RST
RST
______________________________________________________________________________________
Mission Example: Prepare and
PD Select
PD Select
PD Select
PD Select
RMC TA
RMC TA
CM
CT
Start a New Mission
FF loop
FF loop
<data to EOP> CRC-16
<00 to EOP>
1-Wire Communication Examples (continued)
CRC-16
<32 bytes>
<32 bytes>
Step 1: Set the RTC (if it needs to be adjusted).
Step 2: Clear the data of the previous mission.
Step 3: Set the search condition and Mission Start
Delay and clear the alarm flags.
Step 4: Set the temperature alarms and write the
Sample Rate to start the mission.
Loop
Loop
CRC-16
CRC-16