so it works for about all allwinner chipped consoles like:
You don’t need to worry about it. But if you really want to know, it’s using FEL mode. FEL is a low-level subroutine contained in the BootROM on Allwinner devices. It is used for initial programming and recovery of devices using USB. So we can upload some code into RAM and execute it. In this way we can read the Linux kernel (yes the NES Classic Mini and Famicom Mini runs an Linux operating-system), write kernel or execute kernel from memory without writing it to flash. So we can dump the kernel image of the NES Mini, unpack it, add some games and run a script which will copy them back to flash, repack, upload and execute. However, the games directory is on a read-only partition. Therefore we also need to create and flash a custom kernel with a special script that creates a sandbox folder on a writable partition and mounts it over the original games folder. This means that your original files are safe: you cannot delete or harm the original files in any way, even if you wanted. For kernel patching my application just executes other applications, which is why there is a “tools” folder.
for some of these devices the this charger port isn't the right starting point to install, but the exploit point in software terms is about the same on all of them.
for PSX mini you for example need a low powered usb pendrive to install it.