DS1921G_11 MAXIM [Maxim Integrated Products], DS1921G_11 Datasheet - Page 26

• Manufacturer Part Number: DS1921G_11
• Description: Logs Up to 2048 Consecutive Temperature Thermochron iButton
• Manufacturer: MAXIM [Maxim Integrated Products]

Thermochron iButton
Figure 11. Mission Start and Logging Process
26
NOTE: THE MISSION START PROCESS IS INVOKED WHEN THE COPY SCRATCHPAD COMMAND IS USED TO SET A NEW SAMPLE RATE BY WRITING TO THE SAMPLE RATE
REGISTER AT ADDRESS 020Dh. ONE MINUTE AFTER THE START DELAY COUNTDOWN IS OVER, THE LOGGING PROCESS BEGINS AND THE MISSION START PROCESS ENDS.
______________________________________________________________________________________
DS1921G COPIES NEW SAMPLE
RATE FROM SCRATCHPAD TO
DS1921G WAITS UNTIL NEXT
MISSION START PROCESS
SAMPLE RATE REGISTER
START DELAY COUNTER
DS1921G SETS MIP = 1;
DS1921G DECREMENTS
MINUTE BOUNDARY
COUNTER = 0?
MEMCLR = 1?
NEW SAMPLE
START DELAY
MEMCLR = 0
RATE = 0?
MIP = 1?
MIP = 1?
EM = 0?
N
Y
Y
N
N
Y
Y
N
N
Y
Y
N
DS1921G SETS MIP = 0
UNTIL NEXT MINUTE
END OF PROCESS
DS1921G WAITS
BOUNDARY
LOGGING
PROCESS
DS1921G
DS1921G WAITS
ONE SAMPLE
Y
DS1921G STORES TEMPERATURE
PERIOD
AT DATA-LOG ADDRESS
DS1921G INCREMENTS
DATA-LOG ADDRESS
ADDRESS = 1800h?
DATA-LOG
N
N
Y
DS1921G UPDATES HISTOGRAM,
MISSION SAMPLES COUNTER
DEVICE SAMPLES COUNTER,
AND ALARM, IF APPLICABLE
DS1921G SETS DATA-LOG
DS1921G COPIES RTC TO
MISSION TIMESTAMP
DS1921G MEASURES
LOGGING PROCESS
ADDRESS = 1000h
END OF PROCESS
TEMPERATURE
MIP = 1?
RO = 1?
N
DS1921G STORES TEMPERATURE
11 BITS OF DATA-LOG ADDRESS
DS1921G INCREMENTS LOWER
AT DATA-LOG ADDRESS
Y