Some things are tricky to do; more than can be explained in a tweet or forum/ blog post. If I write some detailed instructions or explanation of something and it needs a little extra room, you will find it here.
The AVGCART is an Atari 8-Bit SD based Multicart. Designed by AtariAge user tmp in 2018. Here is your guide to everything AVGCART.
The SDrive-MAX is an Arduino based floppy disk and cassette drive emulator for the Atari 8-bit range of computers, and this is everything you need to know about it.