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I2C issue

Posted: 19 January 2011, 1:04 AM
by FFMan
I have 2 devices connected on an I2c chain. One is a 8 x 30 character lcd display, and the other is an sd card module.

I can get either to work independantly, but if i try to send data to one, then the other device several times a second, i either see the sd card module not accepting commands and/or garbled data on the lcd screen.

My suspicion is poorly implemented I2c on the one or both of the devices, they are both from the same source and I have had issues with clockstretching not working properly in the past. Is there anything i can do, apart from considering using 2 i2c channels on different pins ?

thanks

Re: I2C issue

Posted: 19 January 2011, 9:09 AM
by dkinzer
FFMan wrote:I have 2 devices connected on an I2c chain.
What are the model numbers of the devices. Do you have links to the datasheets for them? Also, are you using the hardware I2C channel or a software-based channel?

Posted: 19 January 2011, 9:17 AM
by FFMan
this is one device http://www.byvac.com/bv3/index.php?rout ... duct_id=65

and this the other http://www.byvac.com/bv3/index.php?rout ... duct_id=80

i'm using software i2c because i am using com2 on a zx24n so no choice.

hope this helps