[Long Term Enhancement] Mapping GPIO Pins for buzzer/Led functionality

[sasines]

Wondering if the use of the GPIO pins could be added. The same or similar as the original HamClock.

1. BME-280 sensors for local environmental conditions.

2. LED that comes on just prior to a selected satellite’s rise in a flashing mode, then on solid while the pass is in progress, then flashing approximately 60 seconds before going LOS. I use this function quite often.

3. Interface to the KX-3 for rig control. I’m running a KX-3 and like this feature.

4. Ten minute timer with GPIO output for LED or buzzer.

I am not at all proficient with Linux. I would be willing to test and help out in any way that would be of use to you. Thank you for all that you are doing. This project is fantastic.

[accius]

Thanks for the kind words and the detailed request. Let me go through each one:

3. KX-3 rig control — ✅ Already exists!

The Rig Listener already supports Elecraft radios (K3, K4, KX3, KX2) via Kenwood-compatible serial protocol. Plug in your KX-3 via USB, run rig-listener, select option 3 (Elecraft) in the wizard, and you'll get click-to-tune from anywhere in OpenHamClock — DX cluster spots, POTA activations, WSJT-X decodes, etc. See the rig-listener/ folder or Settings → Rig Control.

1, 2, 4. GPIO (BME-280, satellite LED alerts, timer buzzer)

This is the one that needs some honest context. Original HamClock is a native C++ application that runs directly on the Pi's framebuffer with direct hardware access to GPIO pins. OpenHamClock is a Node.js web server + React browser app — it's architecturally very different, and doesn't touch hardware directly.

That said, it's not impossible. The approach would be a lightweight GPIO companion service (similar to how rig-listener bridges serial radios) that:

• Exposes an HTTP API on localhost
• OpenHamClock server pushes events to it (satellite AOS/LOS predictions, timer ticks)
• The companion drives GPIO pins via pigpio or onoff

The satellite pass data is already computed client-side from TLE propagation, so the prediction math exists — it's a matter of surfacing AOS/LOS event hooks server-side and bridging to hardware.

I'm going to leave this open and label it as a longer-term enhancement. The BME-280 and satellite LED features would genuinely be cool for shack Pi setups. If anyone in the community has experience with Node.js GPIO libraries on the Pi and wants to help prototype a companion service, that would be a great starting point for a PR.