I have a Creality CR-10S. I’ve never actually looked inside the control box, so I took it apart tonight. It’s not built out of a standard Arduino board board in a socket, its a custom board with the CPU on it. The CPU is an ATMega5460, which is indeed an Aduino supported CPU. The USB connection is actually just a standard Arduino USB-to serial converter. I bet when you plug your PC into the printer, a new serial port appears in Windows, even though your printer firmware is insane. (What printer do you have?)
This means the Arduino IDE can probably load it, but only if the bootloader in the chip is sane. I imagine Cura just includes an Arduino loader that it uses to update firmware just like the Arduino IDE does. So I expect that since Cura can’t load the firmware, neither will the IDE. But it might be worth trying the IDE to see if it can load anything. What do you have to lose? Your load is already corrupted, so this won’t make it any worse. There are plenty of little demo programs in the beginners tutorial. If you can load any one of them, then your bootloader is ok (See https://www.arduino.cc/en/Guide/HomePage ). Don’t keep it running the tutorial load any longer that you have to.This load doesn’t understand the printer hardware, so it might turn on the nozzle heat or something, and with no temp regulation firmware, it could eventually cause a fire.
If you can t load anything, then the bootloader is probably toast. Aside – how did the bootloader get corrupted – did your update say anything about updating the bootloader?
If the bootloader is corrupted, then you’ll have to get your hands dirty now. This next bit involves opening the control box and removing the power supply to get at the programming connector. Obviously, remove the power cord from the back of the control box before you open it. You’ll need 2 different sizes of Allen Key to do this on a CR-10.
You can either buy a programming cable (search for “ICSP Cable”, and you’ll find lots). you can also build your own if you want, out of another Arduino. Either way, see https://www.instructables.com/id/Flashing-a-Bootloader-to-the-CR-10/ If you can successfully install a bootloader, then I suspect Cura will once again do the printer firmware update (using the right file this time! 🙂 ).
Or, find a friend who’s Arduino knowledgeable and ask her to do all the above 🙂