add more SRAM to atmega 644

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#1
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Hello,
I am looking for a way to add more physical SRAM to an Atmega 644 chip.
I read that it's possible with some limitations, as the compiler allow this in some way:

http://www.nongnu.org/avr-libc/user-manual/malloc.html

Now, is there any example on what SRAM chip to use, and how to interface it with an AVR ?
Any advice on this subject ?
thanks,

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obor00 wrote:
I am looking for a way to add more physical SRAM to an Atmega 644 chip.
Unless the microcontroller has an external memory interface (which the mega644 does not) you'll have to use a RAM chip with a serial interface (e.g. SPI) or "bit bang" a parallel interface. Either way, the result is not the same as adding external RAM to a microcontroller that has an external memory interface (e.g. mega1281, mega1280, etc.). In particular, without the external memory interface there is no way for the compiler to generate code to access the external RAM.

Don Kinzer
ZBasic Microcontrollers
http://www.zbasic.net

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Thanks dkinzer.
Is there an example, or a how to add external SRAM on a mega1280 (or equivalent) somewhere ? Hardware connection and/or specific linker options ?
Thx