orgua/OneWireHub

Stability / timing issue

Opened this issue · 1 comments

JochenKoehler69 commented

I tried to run a combination of your DS2450 and DS18B20 examples on an Arduino Uno (actually it's a clone from AZ-Delivery ).
First, the connection to my OW-Master (USB-adapter DS9490R) was not stable - the DS2450 appeared and disappeared and the DS18B20 was not visible at all.
Then I changed ONEWIRE_TIME_MSG_HIGH_TIMEOUT to 30000ms (Factor 2) and then both sensor have a stable connection!
However I realized that the blinking LED frequency seems to be half now.

  • What's the reason for that?
  • Do I need any countermeasures for that or can this be ignored?

Thanks

djungelorm commented

I came across a similar issue trying to use the DS18B20 example connected to a Raspberry Pi Zero. Looking at the bus traffic using a scope I can see that the Pi sends a reset, then waits 30ms before it sends the search command. Increasing ONEWIRE_TIME_MSG_HIGH_TIMEOUT to >30ms fixes the issue in this case as well.