Connecting 2 or more masters to an I2C bus

Pedro

Hi all,
I need to connect two or more BS2P to an I2C bus, and they all need to access an eeprom 24lc640.
How can I arbitrate the BS2p's.

Thanks

Jon Williams

You would have to do it manually (writing your own I2C routines) as I2CIN and I2COUT don't support multi-master configurations.

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Jon Williams
Applications Engineer, Parallax

Pedro

I'm a newbie with I2C, could you send me a sample?

Post Edited (Pedro) : 9/13/2005 12:12:44 PM GMT

Jon Williams

I don't personally know how to do it, you'd have to look-up the I2C spec. I know that it MM has been done with the Javelin Stamp -- but that code is in Java and if you're new it may not be helpful. Manually implementing standard I2C communications isn't hard, and I've attached and example for you to start your project from.

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Jon Williams
Applications Engineer, Parallax

Paul Baker

Check out these documents on how to do multi-master I2C, pay attention to the arbitration sections.

http://www.mcc-us.com/i2cHowToUseIt1995.pdf

http://www.semiconductors.philips.com/acrobat_download/applicationnotes/AN10216_1.pdf

http://www.cse.ucsc.edu/classes/cmpe123/Fall02/Files/I2C_BUS_SPECIFICATION.pdf

http://www.esacademy.com/faq/i2c/

http://www.semiconductors.philips.com/markets/mms/protocols/i2c/

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