5 Probe issues to work out — SUMMARY OF THEM (DS18B20) September 12, 2011Posted by rik94566 in aquaponic automation, aquaponics, arduino, DIY aquaponics, DS18B20, indoor aquaponics, indoor gardens, One-wire, Stainless Steel Temp Probe, Temperature Probe.
Tags: aquaponic automation, aquaponics, arduino, arduino sketch, automation, DIY aquaponics, DS18B20, electronics, indoor aquaponics, indoors aquaponics, rik kretzinger, sensor, Temp Probe, Temperature Probe
Now that I have loaded up 5 probes and attempted to read all of them a number of issues surfaced for me. I am going to summarize them here and then work through each one of them and see if I can resolve them as I move forward to my end goal of building a CAT5/RJ45 hub for 5 DS18B20 temp probes that are read using only one digital pin on my arduino. Once completed this hub could be used and built by anyone with basic skills. The hub could be used in home automation / aquaponics / or wherever else needed.
When errors occur with probes there needs to be away to highlight the problem and with which probe.
ONE-WIRE LIBRARY – deviceIndex:
This is the feature inside ONE-WIRE LIBRARY that to me appears to control what probes get read and when. Found that it has a mind of its own.
There has been references to the fact that as probe count goes up so does the requirement for resources that arduino supplies to the senors.
Similar to the resistor situation power demand increases as you add more probes.
I do not think the sketch I am using is that large to cause a crash. So the crash has to be from a resource constraint of some type. My programing skills are very limited at best, so I have to keep my code very basic. It is my feeling that a lot of other people are programing challenged like me and this one fact is keeping a lot of folks from real development of some awesome projects. So until I get better or find someone to help out I will keep on keeping my sketches simple and work with what has worked for others and only change a few lines as needed.
THE WAY FORWARD:
Once I blog about the above items, I will be moving in a new direction regarding the probes and how they get read. Going this way will allow me to be very specific for each probe and more in line with current practice when using DS18B20 protocol.