DS1621 Datasheet, PDF (12/16 Pages) Dallas Semiconductor – Digital Thermometer and Thermostat

MEMORY FUNCTION EXAMPLE
Example: Bus master sets up DS1621 for continuous conversion and thermostatic function.
DS1621
BUS MASTER
MODE
TX
TX
RX
TX
RX
TX
DS1621
MODE
RX
RX
TX
RX
TX
RX
RX
TX
TX
RX
TX
RX
RX
TX
TX
RX
RX
TX
TX
RX
RX
TX
TX
RX
RX
TX
TX
RX
TX
RX
RX
TX
TX
RX
RX
TX
TX
RX
RX
TX
TX
RX
RX
TX
TX
RX
TX
RX
RX
TX
TX
RX
RX
TX
TX
RX
DATA (MSB
FIRST)
START
<address,0>
ACK
ACh
ACK
02h
ACK
START
<address,0>
ACK
A1h
ACK
28h
ACK
00h
ACK
START
<address,0>
ACK
A2h
ACK
0Ah
ACK
00h
ACK
START
<address,0>
ACK
EEh
ACK
STOP
COMMENTS
Bus Master initiates a START condition.
Bus Master sends DS1621 address; R/ W = 0.
DS1621 generates acknowledge bit.
Bus Master sends Access Config command protocol.
DS1621 generates acknowledge bit.
Bus Master sets up DS1621 for output polarity active
high, continuous conversion.
DS1621 generates acknowledge bit.
Bus Master generates a repeated START condition.
Bus Master sends DS1621 address; R/ W = 0.
DS1621 generates acknowledge bit.
Bus Master sends Access TH command.
DS1621 generates acknowledge bit.
Bus Master sends first byte of data for TH limit of
+40°C.
DS1621 generates acknowledge bit.
Bus Master sends second byte of data for TH limit of
+40°C.
DS1621 generates acknowledge bit.
Bus Master generates a repeated START condition.
Bus Master sends DS1621 address; R/ W = 0.
DS1621 generates acknowledge bit.
Bus Master sends Access TL command.
DS1621 generates acknowledge bit.
Bus Master sends first byte of data for TL limit of
+10°C.
DS1621 generates acknowledge bit.
Bus Master sends second byte of data for TL limit of
+10°C.
DS1621 generates acknowledge bit.
Bus Master generates a repeated START condition.
Bus Master sends DS1621 address; R/ W = 0.
DS1621 generates acknowledge bit.
Bus Master sends Start Convert T command protocol.
DS1621 generates acknowledge bit.
Bus Master initiates STOP condition.
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