Hi Richie, nice to see our paths are crossing again! I've spent the last two months working on a way to serve files from a Teensy over WiFi using a ESP* chip. My project is close to working but I've been stuck on ESP32 mutitasking/multicore issues for the last couple weeks. As of now I can:
- Connect my Teensy 4.1 with microSD card to an ESP32 using a serial port (two wires only)
- Run a slightly modified ESP_AsyncFSBrowser sketch on the ESP32, which can interact with a remote filesystem connected over serial (the Teensy 4.1's SD filesystem), and serve files from the remote filesystem
- Download files over WiFi using the browser or curl with >50% success rate, but occasional missing bytes (because of the multitasking/multicore issue I've been stuck on)
An underwhelming image, but this shows two filesystems being served to a webpage, "SD" is the local SD on the ESP32, "myfs" is the Teensy's SD. When a file is loaded there's a preview/editor usable on the right side.
I've given up on fixing the occasional missing bytes, and I'm now focusing on making the serial link reliable with error checking and retransmits if needed, which should hopefully compensate for the missing bytes issue. I need to add support for uploading/editing files too which should be relatively easy.
I'm working with an ESP32 dev board right now, but believe this should work just as well only slower on an ESP8266, e.g. a $2 ESP-01 module. I haven't tried using an Airlift yet, but I have an Airlift dev board and since it only needs two pins to connect it should work just fine with Airlift, and I'll verify at some point.
This isn't exactly what you asked for, but I think will solve the problem of retrieving files from your Teensy over WiFi. If you want to upload files to a remote server, I suggest getting that functionality working with an ESP32, uploading files from a local file system (e.g. LittleFS stored in flash), and then you can switch to the remote teensy filesystem once my library is more stable. What I'm working on won't directly help you run code on the Teensy that pushes files to a remote server though I found an (out of date) project that does that:
https://github.com/jeelabs/esp-link