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Johnrh
01-05-2006, 10:24 AM
······ hey, does anyone know if you can connect more than one I2C device (say the 16K EEPROM part number·<!--StartFragment --> 602-00013 (http://www.parallax.com/detail.asp?product_id=602-00013) ) to the same two I/O pins?

Thanks for the Help.

John

Chet
01-05-2006, 11:00 AM
Have a look at this:

http://www.parallax.com/dl/docs/prod/oem/24LC128-v2.0.pdf

Parallax has it all.....

Chet

Loopy Byteloose
01-05-2006, 11:32 PM
Mutiple I2C chips·require different addresses. Unlike SPI [which has·single 'chip select' wire to each device], it is·sometimes called up in software [NOTE -- I may be confusing One-wire and I2C.· True I2C appears to only have 3 address pins and not a software address function.]

Some devices, like EEPROM·would get bogged down a bit by the need to call its address in software to get its attention and to exclude other devices.·

You will note that the EEPROM has three 'Address Pins' and these allow it to share with up to 8 similar devices.· There is no internal 'software address'.

If you have few devices, you can just pull the unused pins appropriately high or low.

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"When all think alike, no one is thinking very much.' - Walter Lippmann (1889-1974)

·················································· ···················· Warm regards,····· G. Herzog [·黃鶴 ]·in Taiwan

Post Edited (Kramer) : 1/6/2006 8:55:57 AM GMT