Re: OneWire issue?
Posted: Tue Sep 25, 2018 8:43 am
It has been many years since using these devices with Dallas one wire. The protocol uses a presence pulse and wire resistance and capacitance and line voltage can cause issues with the shape of this pulse.
If the unique device id is known the connection is established with less error.
If the search is used then an elaborate decision tree is used and is subject to a single point of failure in response or timing from all connected devices. Also the devices can use parasitic power ( no separate power supply to the device) which is very susceptible to long wire resistance and poor connections.
This is where a scope earns its value.
If the unique device id is known the connection is established with less error.
If the search is used then an elaborate decision tree is used and is subject to a single point of failure in response or timing from all connected devices. Also the devices can use parasitic power ( no separate power supply to the device) which is very susceptible to long wire resistance and poor connections.
This is where a scope earns its value.