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phillip v
01-23-2008, 06:56 AM
I was showing my hydra to a friend and talking with him about it and the stuff that comes with it when he asked me if a bigger eeprom could be added to the hydra???? and how big???? I myself don't see the need with the sd comeing out real soon...

Paul Baker
01-23-2008, 07:10 AM
The 128KB represents the current maximum size for serial I2C eeproms. Beyond 64K, bits from the command byte must be stolen in order to have enough address bits. You can attach upto 3 more 128KB eeproms on the same bus and be able to access·all of them. Each must have a unique value for A0 and A1 in order to have them each addressable. Additionally with the Hydra, the onboard 128K gets remapped from 00 to 01 and the expansion card eeprom occupies 00. This means in order to maintain the current functionality, only two additional eeproms may be added and they must occupy 10 and 11.

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Paul Baker (mailto:pbaker@parallax.com)
Propeller Applications Engineer
[/url][url=http://www.parallax.com] (http://www.parallax.com)
Parallax, Inc. (http://www.parallax.com)

Post Edited (Paul Baker (Parallax)) : 1/23/2008 12:15:19 AM GMT