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Ron Marcus
- 22nd December 2007, 19:34
I have an LCD 16x2 display that uses I2C for an interface. I have only used I2C with eeproms, and the data sheet is poorly translated from Chinese and is scant at best. Has anyone used an LCD display with I2C and care to share some example code?
Thanks,
Ron

mister_e
- 23rd December 2007, 19:59
Which LCD are you using?

Ron Marcus
- 23rd December 2007, 20:15
Hey Steve,
I finally found out the display uses the ST7032i driver chip. I found the manual on line, and it was much more detailed than the info for the 2x16 module, plus, the writer actually knew english rather than putting it through a translator.
The fact that it ties up two pins, runs from 3.3 volts, and is only 1.7" wide by .1" thick, makes it worth while figuring out.
I will etch a break out board, and get to work.
Thanks for the reply,
Ron

Ron Marcus
- 29th December 2007, 14:53
I did get the display to work, but it is acting odd while using the I2Cwrite command. I will more than likely roll my own I2C routine, but I would like to understand why the standard instruction will not work. Anyone played with this and know in what sequence the bytes are sent out? The LCD requires an eight bit address byte, followed by an eight bit control byte, then any data. Reading the I2C info in PBP, it looks like a control byte is sent first. I made the control byte the address byte using an eight bit variable, and this works, but it looks like the next byte is misinterpreted.
Thanks,
Ron