Crazy printer firmware issues

Hello, I'm super new to this whole thing and have had nothing but bad luck. I have no idea if there is a proper thread for this, but I've been trying to flash new firmware to my 3d printer and have run into many issues with the arduino side of the process. I am using an Arduino Uno.

Following many tutorials, and trying to use the recommended Lauszus-Sanguino pack (which kept giving me a "current board needs the core arduino:arduino that is not installed" error)

I got stuck at burning the bootloader, which I eventually resolved. Now, when flashing the firmware, I keep getting an error while using the Mightycore pack.

I am trying to flash the latest Marlin 1.1.x using Arduino 1.8.7 and I keep getting

'DIO38_RPORT' was not declared in this process.

I'm somewhat code illiterate and have no idea what that means or what to do. My printer board (ATmega 1284p on creality V1.1.2) is basically a brick unless I can get this figured out. Any help would be greatly appreciated. I am not asking for support for the printer, just trying to figure out what arduino is having trouble with.

I am a super noob at this and realize I may have done something wrong even though I followed every step of the tutorials very carefully, things just didn't work for me the same way as the tutorials expected. It seemed like an easy enough process, and I don't particularly have much interest in learning programming. I just want my printer to work.

Please let me know if I'm somehow posting this wrong or in the wrong place or whatever. Thanks all.

I have no idea if there is a proper thread for this, but I've been trying to flash new firmware to my 3d printer

There is. It would be on your printer's site, NOT here.

I am trying to flash the latest Marlin 1.1.x

Does that even work on a Uno? Most printers use Megas.

Try a Google search for: installing marlin on creality

It might help to specify the model of Creality printer.

I have been rummaging around Google for days now and haven't been able to find the information or error types I need. It is a CR10s. Every guide I've looked at says the uno should work fine, but I have run into errors and problems that nobody else seems to get.

There is. It would be on your printer's site, NOT here.

There is no support or forum on the printer site, that is why I've posted here. Also, I'm having trouble with the Arduino side of the process, not the printer side.

recipe.preproc.macros pattern is missing

Error compiling for board Sanguino W/ ATmega1284 or ATmega1284P (16MHz).
The current selected board needs the core 'arduino:arduino' that is not installed

Have you looked at the RepRap Forum where they specialize in 3D printing?

...R

The references I see to the Creality CR10S say that if uses the ATmega2560 (Arduino MEGA 2560) processor. Are those references out of date and they changed the board to use the ATmega1284 (Sanguino)? Can you find the main processor chip and check the model name?

The references I see to the Creality CR10S say that if uses the ATmega2560 (Arduino MEGA 2560) processor. Are those references out of date and they changed the board to use the ATmega1284 (Sanguino)? Can you find the main processor chip and check the model name?

I think I may have somehow gotten an odd setup when I ordered it. The default board has an Atmel ATmega 1284p and the whole main board has a slightly different component layout than pictures I've seen.