Is it possible to have a slave\master and use a i2c lcd, using the wire.h library. Can't seem to get the lcd to work, the lcd just seems to freeze Some sites say its is possible others say use a different library ??
I think you need the proper library for the lcd in question.
You need to know exactly how the lcd works in order to code with wire.h and make it work (too hard for beginners and this is why we have libraries).
We could give better answers if we knew exactly what LCD that you have and more details about your setup.
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The LCD is a slave by design. Another slave cannot control the bus or another slave. It has to be a master to do that. Start with a simple example sketch to check your hardware. Preferably with the I2C scanner and see if it is recognized, then if so some simple code to drive the display. Yes there are several libraries that work and several that do not, with the same name.
Hi thanks for the reply, did start with a simple sketch, just using a pot on one of the uno's with a 16 02 I2C lcd, ( with wire and LiquidCrystal_I2C libraries) which worked fine. The tried to add a slave\master and the lcd would just freeze , think you migth be right in that have the slave master wrong way round !?
Sorry, that really does not make sense.
What are you trying to say?
Sorry - typo - should be I Then tried to add a slave\master and the lcd would just freeze , think you migth be right in that have the slave master wrong way round !?
Hi,
Do you mean you have the LCD running on I2C okay.
BUT
Want to communicate with another I2C component in master/slave type comms as well as have the LCD operating?
If so, what is the other component/device?
Tom.... 
I would like to be able to communicate in master\slave and read values from a pot in order to work a dab radio shield, but can't past "first base" at the moment, ie read pot on slave - lcd on master.
Hi,
The Arduino controller is the master.
You have 2 slaves, 1st is the LCD the 2nd is the digital pot.
Tom...
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