Dallas DS1820, Инструкция

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DS1820
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MEMORY FUNCTION EXAMPLE Table 3
Example: Bus Master initiates temperature conversion, then reads temperature (parasite power assumed).
MASTER MODE DATA (LSB FIRST) COMMENTS
TX Reset Reset pulse (480–960
µ
s).
RX Presence Presence pulse.
TX 55h Issue “Match ROM” command.
TX <64–bit ROM code> Issue address for DS1820.
TX 44h Issue “Convert T” command.
TX <I/O LINE HIGH> I/O line is held high for at least 500 ms by bus master to
allow conversion to complete.
TX Reset Reset pulse.
RX Presence Presence pulse.
TX 55h Issue “Match ROM” command.
TX <64–bit ROM code> Issue address for DS1820.
TX BEh Issue “Read Scratchpad” command.
RX <9 data bytes> Read entire scratchpad plus CRC; the master now recal-
culates the CRC of the eight data bytes received from the
scratchpad, compares the CRC calculated and the CRC
read. If they match, the master continues; if not, this read
operation is repeated.
TX Reset Reset Pulse.
RX Presence Presence pulse, done.