Author Topic: RFM69 library extensions for finer power granularity with RFM69-HW (RFM69_ATC)  (Read 13034 times)

SaffellBot

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I didn't realize that the codebender code wasn't necessarily maintained. It worked fine without ATC. I've updated the RFM69 library as a personal library from github and it compiles now. Thanks!

Felix

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Yup that may be an option to override theirs with your own variant, which at least is good that they have that feature.

ssmall

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Is it possible to dial back the power on a RFM69HCW so that the power consumption is similar to the RFM69CW using the RFM69_ATC library?  Or is this post still the case?

https://lowpowerlab.com/forum/rf-range-antennas-rfm69-library/rfm69-library-extensions-for-finer-power-granularity-with-rfm69-hw-(rfm69_atc)/msg4055/#msg4055

Felix

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Can you clarify exactly what you mean by: similar to the RFM69CW
And I'd be curious to know where you see a case for that. Maybe really close range?

TomWS

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Is it possible to dial back the power on a RFM69HCW so that the power consumption is similar to the RFM69CW using the RFM69_ATC library?  Or is this post still the case?

https://lowpowerlab.com/forum/rf-range-antennas-rfm69-library/rfm69-library-extensions-for-finer-power-granularity-with-rfm69-hw-(rfm69_atc)/msg4055/#msg4055
According to that post and my feeble recollection, it isn't possible to go below -2dbm output, despite the claim on page 21 of the datasheet.  The PA0 only setting is not routed to the antenna on the module, IIRC, and therefore doesn't produce any useful signal.  It is too bad, I had hoped that ATC could have covered the entire -18 to +20dbm range.  It might be worthwhile experimenting to verify this however.


Felix

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TomWS is correct, in that physically the HCW variant is routed to certain amplifier pins of the module which enables it to reach 20dBm output, but does not allow it to go to the lower range of the CW. That is why there is a HCW (up to 20dBm) and a CW (up to 13dBm).

An observation RE ATC:
I see that when the ATC does actually need to kick in, it is best to go 10 steps up per retry or even up to max, depending on scenario, to ensure delivery. I have thus modded the lib to allow this.
That is where HCW is more useful to have 7dBm extra power, a max of 100mW output, vs just 20mW of the CW. On the lower end, the HCW is still very low power.

ssmall

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I was just wanting to understand the difference between CW vs HCW from a power consumption perspective.  Thanks for clarifying.