SLAU723A October 2017 – October 2018 MSP432E401Y , MSP432E411Y
1-Wire is a simple single-wire communication interface comprising a wire protocol, transport protocol, and base session protocols (as well as some basic commands). The wire protocol generates 0 s and 1s by varying the time the line is held low (it is pulled up by a resistor). The MSP43E microcontroller is the master and controls the line at all times. A pull-up keeps the line parked high and the microcontroller driver is assumed to be normal open-drain. No special GPIO configuration is needed here since the open-drain support is taken care of outside of the microcontroller. See Table 17-2 for pin configuration information. Data can be both read and written on the same 1-Wire pin. The 1-Wire module supports the most basic aspects of the protocol, including wire protocol, byte transport control and line reset. Software is expected to handle the session protocol, including selection of a slave (when more than one is on the same line) and higher level commands.
NOTE
All time values by the 1-Wire Master are stated in μs, but the actual time on the wire may be less by 62.5 ns.