donutswdad has just released the “gSerial Enabler” (gSE) – A device that installs in any of the gscart/gcomp switches with an EXT port and allows them to be controlled by the RetroTINK 4K’s serial commands. You can make your own via the open source project on Github, or purchase pre-made kits directly from the developer. The kits are about $40 and include the gSE, a passthrough adapter that connects to the RT4K’s VGA input, wile also allowing VGA cables and adapters to still be used, as well as a cable to connect them. More info below the links:
Purchase Here: https://ko-fi.com/donutswdad
Open Source Files: https://github.com/svirant/gSerialEnabler
To install the gSE hardware, you’ll need to remove the top of your gSwitch, then “plug” the board into the ext port (NOT the jtag port!) by aligning the pins to the port. Make sure to install the aux/serial cable before putting the case back on and route it out via whichever side is best for your setup. Then re-install the top of the case and allow the plexi itself to hold the gSE in place. Finally, connect the passthrough adapter to the RT4K and connect the aux cable. As a note, the gSE is powered by the switch, so no other cable is needed; The USB-C port is just for future firmware updates.
Software installation is the same as all RT4K auto-switching methods – First, make sure you’re on the latest firmware with “Auto Load SVS” enabled in the Profiles menu. Then, create a /profile/SVS/ directory and copy your existing favorite profiles for each console (or make new ones). Rename the profiles: “S201_<user defined>.rt4” – “S208_<user defined>.rt4” for Inputs 1 – 8 respectively.
You can actually connect up to five gswitches to allow for auto-switching via a headphone jack splitter, however you’ll need to re-flash the gSE’s firmware with offset variable set so SVS profile numbers don’t overlap. While setting up one gswitch seems really easy, multiple switches are obviously harder to configure, so refer to the Github manual for that.
