Getting Started with the PicoGUS Femto Edition
If you've purchased a PicoGUS Femto Edition from my Tindie store or built your own with the design files in this repository, here's how to get started.
The PicoGUS Femto Edition (or just the "Femto") is a miniaturized version of the PicoGUS that is designed to plug into the ISA expansion connector on the Hand386 handheld computer, as well as the one on the Book8088. It also can plug into an ISA adapter to be used in a normal retro PC with ISA slots. The Pico being outside of the computer case means WiFi reception is good – emulating an NE2000 card over WiFi is on my firmware support roadmap!
The Femto board has a few jumpers on it - one labeled "RESET EN" for reset enable, and one to enable power on the Pico's USB port. The jumper should almost always be on reset enable – if you are using your Femto on a Hand386 and are getting odd behavior, try removing this jumper. The USB OTG power jumper can be enabled if and only if you are using a USB device like a joystick with your PicoGUS. Use a commonly available micro USB OTG cable to plug your USB devices in. (Joystick support is also on the roadmap!)
Plug your Raspberry Pi Pico (with headers) into the socket on the Femto. Be sure to orient it so the Pico's USB port is aligned with the "PICO USB vvv" marker. If you plug it in backwards, you will fry your Pico!
Program your Pico with the PicoGUS firmware from the latest release by holding the BOOTSEL button down on your Pico while plugging it into your computer, then dragging the .uf2 file onto the "RPI-RP2" drive that appears on your computer.
The Femto has a 2.5mm TRS MIDI jack on it, wired for the "Type A" standard. If you want to use MIDI devices that use the standard DIN5 connector on it, you'll need an adapter. If you're in the US, I recommend this adapter cable from Quilter Labs.
The Femto Edition ISA adapter also has a standard wavetable header on it, so you can plug in any Waveblaster-type MIDI synth into it. The audio volume of the wavetable is controlled by the thumbwheel, and is mixed with the audio on the PicoGUS on the "Mixed audio out" 3.5mm jack.
The rest is covered on the Configuring and using your PicoGUS page!