DS1721 Datasheet, PDF (12/16 Pages) Dallas Semiconductor – 2-Wire Digital Thermometer and Thermostat

DS1721
SAMPLE COMMAND SEQUENCE Table 5
Example: After power-up, initiates a temperature conversion, bus master reads temperature
BUS MASTER DS1721 DATA (MSB COMMENTS
MODE
MODE
FIRST)
TX
RX
START Bus Master initiates a START condition
TX
RX
<address, 0> _{Bus Master sends DS1721 address; R/ W = 0}
RX
TX
ACK
DS1721 generates acknowledge bit
TX
RX
51h
Bus Master sends start convert T protocol
RX
TX
ACK
DS1721 generates acknowledge bit
TX
RX
START Bus Master initiates a repeated START condition
TX
RX
<address, 0> _{Bus Master sends DS1721 address; R/ W = 0}
RX
TX
ACK
DS1721 generates acknowledge bit
TX
RX
AAh
Bus Master sends read temperature protocol
RX
TX
ACK
DS1721 generates acknowledge bit
TX
RX
START Bus Master initiates a repeated START condition
TX
RX
<address, 1> _{Bus Master sends DS1721 address; R/ W =1}
RX
TX
ACK
DS1721 generates acknowledge bit
RX
TX <1 data byte> DS1721 transmits MSB of temperature
TX
RX
ACK
Bus Master generates acknowledge bit
RX
TX <1 data byte> DS1721 transmits LSB of temperature
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