Is there any way to dump/backup a SegaCD RAM cart?

You are incorrect about the size.
It is a 1Mbit cartridge, The first file I uploaded was the entire cartridge.
The second file was the cartridge, plus the empty space that was left in the megadisk's RAM, which is 16Mbits.


My cartridge may just be empty, if there is no data in the files.

**EDIT**

I got a Sega CD today, and it confirmed my fear. The ram cart wasn't just empty, it wasn't even formatted!

It took the format well, and I copied-over a few saved games, that were on the system's memory. I will dump it again a few times, so comparisons can be made between when the cart is empty, and when it has a game save on it.

 

Nah. Spot on about addressable memory size. You're confusing that with cart size. The question is where is that 128k cart located in that 16MB of space. If it's a $0 then you dumped it when you used your cart dumper. If it's at $4000000 like the source you cited seems to say then your dump of $0-$200000 missed it by a mile.
You can check by comparing the first 16k of your first dump with the first 16k of the dump after you formatted. If they're the same then it's not at $0.

 

I looked at the two dumps with a hex editor and I don't think it actually dumped the cart's contents. Going by the virtual RAM cartridge file that multiple SegaCD emulators produce, they all had the phrase "SEGA_CD_ROM RAM_CARTRIDGE___" at the end. Nothing like this was in either of the two dumps, and there were patterns of trash data that do not appear in the emulator-created RAM cart files.

 

I can't speak to memory addresses, as I don't have much knowledge of programming.

I can now use the transfer cable, as I have the Sega CD unit.

I will attempt to dump the cart in every way I can, and give you a description of what should be there, but hex editing, isn't something I have knowledge of, as much as, I know what hex is, as a number system, and how to convert back-and-forth to binary. I also have a basic knowledge of logic gates, Boolean logic, and logic tables.

 

If you post the dumps I can easily compare them. If they don't have the save data I'll look into it further. If the cart is in the place it' said to be a byte or so of hex editing to the dump program would let you dump that.