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Topic: external RAM for arduino? (Read 1 time) previous topic - next topic


Does anyone have suggestions for easy/simple/cheap (yeah, pick one or two) RAM solutions for the Arduino?  I'm not talking about flash, EEPROM, or FRAM which all have a limited number of write cycles and are slow.  I need several kB.

I'd like to have a serial (preferably SPI) interface so as not to occupy too many pins.  I could probably use a couple of shift registers and connect a parallel RAM of some flavor, but I would like to keep the component count low.

I've done a bit of googling with no luck.  Any suggestions?



not sure if the chip is comparable, but these guys  are using 32K external ram on an Atmeaga 128...


Thanks, but this is standard parallel memory; that 32k SRAM takes 16 lines for addressing, 8 for data, and 3 more for control, which uses roughly 100% of available I/O on the arduino.

I guess I could make my own "SPI SRAM" by using a dedicated ATmega8 in SPI slave mode and a typical SRAM, but I'm hoping for something a bit simpler.



Have a look at http://elm-chan.org/works/vp/report.html
First check if the component is still available.

I hope this will help



Not that I could give any advice on how to make it work, but in browsing Jameco's catalog I see EEPROM and FLASH memory in serial versions.  For example, the ST Serial flash memory I am looking @ is 20MHz, 3V, SPI bus for <$2.00 (#659913).

I would like very much to be able to hook up extra memory to the serial pins too.


There's a tutprial on using an SPI interfaced flash chip - see http://www.arduino.cc/en/Tutorial/SPIEEPROM .

Flash and EEPROM are slower than RAM but, more importantly, they have a fixed number of write cycles before they fail.


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