Rfg100

[DorrisMancer]

I've got a large'ish Evohome system and have recently acquired an RFG100 as part of a box of bits, can it be used for anything useful (such as monitoring)?

[DarkV]

The RFG100 is for older Evohome systems that don't have build in WIFI.

If you've a new system an RFG100 is useless.

[bruce_miranda]

The RFG100 is super useful even on the most recent version. But you will need to hack it a bit to get the serial data from it and then you can use it as an Evohome monitor.

[DorrisMancer]

I thought I recalled reading something about being able to use it as a monitor. Where can I find guidance on what to do?

[bruce_miranda]

How handy are you at electronics? This isn't a plug and go solution

[DorrisMancer]

4 years studying for an Electronic Engineering degree in the 70s, later CEng and FIET, but my hands-on days were a while ago ;-)

[gordonb3]

Oh, this is pretty interesting. Does the hack destroy the original functionality? Would be nice if it's a simple job of attaching wires to measuring points on the board. Even better if you could also send commands through that serial connection.

[bruce_miranda]

You won't be able to send commands easily because the current MCU on the RFG100 is connected to the radio chip. But you can sniff the data that is has been picked up by the radio as valid on its way to the MCU on board.
It's a fun project. However its not a cost effective one. These parts are all pretty cheap and you can make a fully functional HGI80 for about a tenner these days.