New User: Where's my memory?

[SoftwareMechanic]

Hello all!

As my title states, I am a relatively new user. I've used single-board computers before (in the form of Raspberry Pi), and recently I've gotten my hands on a Lime2 board.

I went through the motions, installed Debian Jessie, as well as the desktop package for it, and now that I have everything up and running I have one issue:

Where's all my memory?

I installed the OS on a 32GB Micro SD card, and the Lime2 board is the 4GB version, but when I use the "free" command, it only shows me having ~1GB available to use total, with over half of that memory being used.

So, I humbly ask all of you experienced users: how do I get access to all of that unused memory, or has it been there all along, and I'm not not looking for it in the right places?

Thank you all very much!

-SoftwareMechanic

[JohnS]

4GB is NAND flash - see product page.

That's not RAM, which it sounds like you're mistaking for.  (Wikipedia etc for what it is in details.)

John

[SoftwareMechanic]

That makes me even more confused. Does that mean I can't use that memory to store things like pictures, documents, etc? All I can use is the RAM?

[Gerrit]

That makes me even more confused. Does that mean I can't use that memory to store things like pictures, documents, etc? All I can use is the RAM?

it means that you CAN use it to store things like pictures and documents, it is non volatile memory not like RAM which is volatile

[MBR]

That makes me even more confused. Does that mean I can't use that memory to store things like pictures, documents, etc? All I can use is the RAM?

From Linux point of view, there are two kinds of memory: the directly addressable one, like RAM and some special kinds of flash memory (e.g. NOR Flash), from which can be data accessed and programs executed directly, and the "memory" accesible as a block device, which are the rest, including disk drives, memory cards and onboard NAND flash memories, where the data/programs must be first loaded into the RAM and then accessed/executed (system can do this transparently via the mmap() syscall). From the user poit of view, these types of memory look more like hard drives than the RAM.

For this case, the onboard NAND flash is accessible as so called Memory Technology Device (see https://en.wikipedia.org/wiki/Memory_Technology_Device), which provide a low-level access similar to the hard disk partitions, but the programs accessing it directly must be aware of bad blocks (yes, NAND flash can have bad blocks) and do some kind of wear leveling, which is handled transparently by MTD-aware filesystem like JFFS2.

[SoftwareMechanic]

Thank you, guys. I think I understand now.

[LubOlimex]

You can store things to the NAND and you can also boot Debian or Android from the NAND memory!

For Android install in the NAND read here: https://www.olimex.com/wiki/A20-OLinuXino-LIME2#How_to_download_new_Android_image_to_the_NAND_memory_of_my_A20_board.3F

For Debian install in the NAND read here: https://www.olimex.com/wiki/How_to_install_Debian_to_NAND

Best regards,
Lub/OLIMEX