Building a LoRa APRS 439Mhz iGate (Part 2)

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Ricardo’s firmware : Power consumption in repeater mode

It’s clear from some of the comments here that the iGate power consumption in repeater mode is a bit high.

I have a spare TTGo-Lora32 do I decided to dig into this a bit and discover what was going on

Here are my findings

  1. We are starting from a base “idle” (non-transmitting) consumption of ~ 140mA
  2. When a failure to connect to any configured WiFi happens, the code sets up an Access point so the user can reach the config page. So far so good. Unfortunately the timeout that can be configured for the AP doesn’t work : there is a bug (recorded in the github issues) that leaves the AP running continously.
  3. The display timeout doesn’t work, leaving the display on continuously
  4. It is possible to put the CPU into “light sleep mode” and save more power this way.

Solutions
2 - Fix the bug
3 - Fix the bug
4 - Leaving the Lora receiver active, enter light sleep for 1 second in the main application loop. Any packets received over RF are buffered in the receiver. On waking, any receive/forward actions are carried out.

The result : average current when idle is now approximately 17mA, of which about 12mA is the unavoidable Lora receiver current.

I am currently testing, but it’s working well so far. Caution : only tested on LORA32 hardware, but should work on any.

I have created a github fork at rickc99/LoRa_APRS_iGate if anyone is interested to have a play. By the way it’s necessary to enable Ricardo’s experimental low power mode in the config.

Cheers
Rick

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