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NMI interrupts of the PC will not guarantee flawless
communication to a 1-wire device through a parallel port
directly, and is discouraged to attempt. As the 1-wire protocol
requires the first 15us of each time slot to contain the data
information, any disruption of this time segment will result in
a communication error. Communicating through the PC
parallel port, as it has been utilized for Dallas Thermal Demo
kits DS1820K and DS1821K, requires timing corrections.
These functions are performed by the DS1481 bus-master. It
translates code from the parallel port to the 1-wire data line,
and buffers data coming from the 1-wire device to the parallel
port:
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