Each 1-Wire slave has stored in ROM a unique 64-bit serial number that acts as its node address device to be individually selected from among many that can be connected to the same bus wire.
About the Protocol
1-Wire protocol uses conventional CMOS/TTL logic levels (maximum 0.8V for logic “zero” and a minimum 2.2V for logic “one”) with operation specified over a supply voltage range of 2.8V to 6V.
Both master and slaves are configured as transceivers permitting bit sequential data to flow in either direction, but only one direction at a time (half duplex); Master initiates and controls all devices
Data is byte-sequential and bit-sequential with data read and written least significant bit (LSB) first signal is transferred in time slots
System clock is not required; each 1-Wire part is self-clocked by an internal oscillator[1] synchronised to the falling edge of the master
Once a device is isolated for bus communication the master can issue device–specific commands to it,
send data to it, or read data from it. Because each device type performs different functions and serves a
different purpose, each has a unique protocol once it has been selected. Even though each device type
may have different protocols and features, they all have the same selection process and follow the
command flow as seen:
[1] Oscillator is mostly electronic device that works on the principles of oscillation: a periodic fluctuation between two things based on changes in energy. Computers, clocks, watches, radios, and metal detectors are among the many devices that use oscillators.
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