Post by thread:I2C problem

Hi, I'm trying to get I2C to work between a pair of PIC16C64 devices. So far, no luck. I have been using the application note AN578 as a guide. My code calls the BSTART subroutine, but it appears that no start condition is ever getting out. The SSP module doesn't seem to be doing anything. Anyone have an idea? Thanks in advance, Lee Holeva

I can figure out how electrically wire up I2C devices easily, but the thing that I don't wholly understand, is the addressing of the slave devices. I mean how do I know what address my certain device uses? Is there something that i need to program beforehand or what? Any help/nudges in the proper direction(s) would be most helpful Sincerely, Jonathan Herr (dracosilv)

Many devices have pins you tie high or low to set the least significant bits of the address. The most significant bits are set by the device manufacturer based on the device type. I'm working with a 24LC256 right now, and it has a few pins devoted to setting the I2C address. Harold {Quote hidden}> I can figure out how electrically wire up I2C devices easily, but the > thing that I don't wholly understand, is the addressing of the slave > devices. I mean how do I know what address my certain device uses? Is > there something that i need to program beforehand or what? > > Any help/nudges in the proper direction(s) would be most helpful > > Sincerely, > Jonathan Herr (dracosilv) -- FCC Rules Updated Daily at http://www.hallikainen.com - Advertising opportunities available!

At 09:25 PM 5/22/2006 -0500, you wrote: >I can figure out how electrically wire up I2C devices easily, but the >thing that I don't wholly understand, is the addressing of the slave >devices. I mean how do I know what address my certain device uses? Is >there something that i need to program beforehand or what? > >Any help/nudges in the proper direction(s) would be most helpful To quote from the I2C bus specification V2.1: "The I2C-bus committee coordinates allocation of I2C addresses". If you just want to use a given chip you read the data sheet to find out the relevant address or addresses for that part. >Best regards, Spehro Pefhany --"it's the network..." "The Journey is the reward" spam_OUTspeffTakeThisOuTinterlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com ->>Test equipment, parts OLED displys http://search.ebay.com/_W0QQsassZspeff