Hi
I am switching to multiple Pi with Emonhub installed to forward data to my own local emoncms server also on a Pi. I was intending to use different groups as some of the radio signals may overlap. I also intend to use different Baseids for the hubs. Is there any limits as to what you can use/choose and are there still suggested ranges that you should stick to?
Regards
Ian
Re: Acceptable Group and Baseid for multiple EmonHubs
Hi Ian
1 to 30 (inclusive) are the available node id's in JeeLib. using different group ids would in theory allow you to use 30 per group but since emoncms is not able to determine which hub or group each input originated from you are still restricted to one set of 30 nodes.
I do not know how many nodes you want to use but if you need more than 30 we can easily edit one emonhub instance to add 32 to all node ids to give you 1-30 and 33-62. This "offset" is to be an inbuilt feature of v2 emonhub to allow multiple networks on one Pi but the principle is the same.
Unless there is reporting to emoncms (by baseid) from the rfm2pi's themselves it doesn't matter if the baseid's are the same on different groups, but it makes no huge difference unless you find yourself short of one node id.
Paul
Re: Acceptable Group and Baseid for multiple EmonHubs
Just to add to that:
"Groups" are still only a software feature. All groups still use the same radio band, so all groups are blocked when a transmitter is any group is transmitting. In your case, using different groups might not help, because the transmissions still must not overlap.
If transmissions are blocking one another, the only recourses you have are shorter messages spaced further apart, or use two frequency bands (433 MHz & 868 MHz) and two receivers.
Re: Acceptable Group and Baseid for multiple EmonHubs
I understood that the group is part of the crc check, so the "wrong group" should only block for as long as it takes to discard any (non-rfm originating or noise) packet that fails crc, if the same group is used then each packet will block for the entire time it takes to be processed on either or both rfm2pi's. Is that not the case ??
Paul
Re: Acceptable Group and Baseid for multiple EmonHubs
"If transmissions are blocking one another"
By that, I meant blocking in the sense of two transmissions coinciding. I got the impression, from the way the original question was worded: "I was intending to use different groups as some of the radio signals may overlap." , that Ian thought that "group" implied a different radio channel, and that's not the case.
Re: Acceptable Group and Baseid for multiple EmonHubs
Hi
Many thanks for the information. I was going to ask Paul if you had to install emoncms in order to use EmonHub and then thought I might as well try and see what happens. The result is I am pretty chuffed.
I have EmonHub only installed on a Pi Zero. EmonHub is posting data to my emoncms.org account, my existing local Pi based server and to my local Pi based test server.
Really appreciate all the work that various people have voluntarily put into this project.
Regards
Ian