I'm running a project that is using the SD library and the TVout library. This uses a lot of SRAM (so I'm told, at least) and I was wondering if anyone can point me in the right direction. Tutorials are greatly appreciated!
Basically the answer is no, there is no way to extend the SDRAM on an arduino.
The Leonardo and Micro that use the ATmega32U4 have 2.5k instead of 2k (500bytes come in handy !)
The Mega2560 has lots more
The Due has even more (but is a 3.3V device)
16K SRAM on 1284P.
Mega can directly support paged SRAM with a shield on the dual-row header.
I want to say 8 pages of 64K each, but really need to check the datasheet on that.
I'd LOVE to have more RAM, The more the merrier! If I could have a 32gig SD card & Gig of RAM on an Arduino? I think I'd be in hog heaven! All the fun of a desktop without the nonsense of the OS to deal with.
-jim lee
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You can have all that on the Raspberry Pi if you run it on Bare Metal, well half a gig of ram anyway.
You may use an external SPI SRAM/FRAM/MRAM, up to 512kBytes per chip (8pin serial SPI). The access is slow however, maybe 10-15usec/byte with a random byte access with arduino. A block access, ie. 512bytes is much faster, maybe 2-3usecs/byte.
Then you may use the 8MB Ramdisk - it requires 11 pins for signals and it is a bit faster than the SPI SRAM (there is a thread in Other HW development forum about it)..
Yes but it is not SRAM, the sort that holds your variables. It is paged storage, this is not what the OP was asking.
@CrossRoads Thanks for the recommendation! It works well and for half the cost of an Arduino Uno $).
I'm not seeing any Mega direct addressable SRAM expansion shields out there at the moment.
I do have a pi.. Could it be setup to run like an Arduino? I find linux to be a pain and and just plain confusing. Command line OSs force you to keep the user interface in your head. My brain is just too small for that.
-jim lee
Could it be setup to run like an Arduino?
No not really. There is Bare Metal, that has no OS:-
http://www.valvers.com/embedded-linux/raspberry-pi/step01-bare-metal-programming-in-cpt1
But better that that there is RISC OS. This is the desktop operating system that all the others stole ideas from. It is a cooperative multitasking system, unlike Linux which is preemptive. It runs a blisteringly fast version of BBC Basic. Just printing a numbered line it goes at about 290 lines per second as opposed to Python under Linux which runs at 6 lines a second. And within a Basic program you can drop into machine code when you want things to really fly.
Extremely responsive desktop where windows can actually be dragged behind other windows, minimised, maximised, dragged off screen or scaled to the size you require.
https://www.riscosopen.org/wiki/documentation/show/Welcome%20to%20RISC%20OS%20Pi