Dallas DS1820, Инструкция

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DS1820
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MEMORY FUNCTION EXAMPLE Table 4
Example: Bus Master writes memory (parasite power and only one DS1820 assumed).
MASTER MODE DATA (LSB FIRST) COMMENTS
TX Reset Reset pulse.
RX Presence Presence pulse.
TX CCh Skip ROM command.
TX 4Eh Write Scratchpad command.
TX <2 data bytes> Writes two bytes to scratchpad (TH and TL).
TX Reset Reset pulse.
RX Presence Presence pulse.
TX CCh Skip ROM command.
TX BEh 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 and the two other bytes
read back from the scratchpad. If data match, the master
continues; if not, repeat the sequence.
TX Reset Reset pulse.
RX Presence Presence pulse.
TX CCh Skip ROM command.
TX 48h Copy Scratchpad command; after issuing this command,
the master must wait 6 ms for copy operation to complete.
TX Reset Reset pulse.
RX Presence Presence pulse, done.