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Topic: shift register with SRAM. speed? (Read 1 time) previous topic - next topic

acmiilangr

Hi all!
I am working on led displays and i'm out of RAM. i tried to use EEPROM and i saw that it is really slow...
I'm gonna use 512KB SRAM (http://www.alliancememory.com/pdf/AS6C4008.pdf) with arduino.

becouse it needs too many pins i was thinking to use shift registers for Address Inputs.

Will i loose much speed?

CrossRoads

Why not use use SPI-accessed Serial SRAM? That will be fast.
Then you don't need all the external shift registers - they're built into the chip.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

acmiilangr

#2
May 29, 2012, 10:24 pm Last Edit: May 29, 2012, 10:51 pm by acmiilangr Reason: 1
these are F-RAM like this? http://www.ramtron.com/files/datasheets/FM25L04B-GA_ds.pdf

i am worring about SPI inteface.

is there any documentary on that?

EDIT:
does this tutorial works the same with FRAM?
http://arduino.cc/en/Tutorial/SPIEEPROM

Nick Gammon

Here:

http://www.gammon.com.au/forum/?id=10979

I calculated the speed as:

Quote
... you can read or write n bytes at the rate of (n + 3) * 3.2 microseconds.


At the rate you need to show data on LEDs that should be plenty fast enough.
Please post technical questions on the forum, not by personal message. Thanks!

More info:
http://www.gammon.com.au/electronics

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