This guide will show how to add support for Internet over WiFi to the MiST FPGA using an ESP8266 Wifi to Serial chip. This has only been confirmed to work on MiniMig but should work the same for any core that can see the MIDI ports as a serial port.
It may also work with earlier MiST's perhaps even faster if you connect directly to the serial header (it has no optocoupler) so let me know if this works with those at faster speeds.
I totally lose all the formatting trying to paste the guide in so here is a link to the google doc. It shouldn't be going anywhere anytime soon: https://docs.google.com/document/d/1FlnxLtpxHlDc56A07uFv0sb5GYEPq3SvTZ7YbWXeQyw
I originally did this with a raspberry pi but found that between the boot time to be able to log into the pi, and the setup required to get into the pi to start PPP, it was not a reliable solution to get connected with. It was also not condusive to auto-starting the TCP/IP stack on boot on the target core.
With the SLIP firmware set up, SLIP is ready on the serial port before the core is done booting, and functions to get connected can be placed in startup. My MiST now gets online and grabs the time off the network on boot.
The maximum reliable bitrate is 38400. I think you can get to 115200 by removing the optocoupler from the circuit somehow, but that gets a little bit more complex.
I am quite curious to know if the Atari ST (MiST) core can use this, and how I would configure something like FreeMiNT to connect to the internet over its "MIDI port".