Mikroe bigavr6 4bit lcd operation

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Hi guys.

I'm at a loss trying to understand why the RW line is connected to GND on the MIKROELEKTRONIKA BIGAVR6 board. It's running in 4bit mode. Shouldn't it be connected to another micro pin like the RS and E lines are?

heres a pic of the schematic to show what I'm talking about.

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Quote:
trying to understand why the RW line is connected to GND
It is a "common" practise if you don't need or want to read anything back form the LCD like status etc. It saves 1 pin.

John Samperi

Ampertronics Pty. Ltd.

www.ampertronics.com.au

* Electronic Design * Custom Products * Contract Assembly

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I was not aware, thanks for that JS.

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About the only thing that you need to use the R/W line for is detecting when the LCD has finished the previous command. Most people just use hard-coded delays instead.

Regards,
Steve A.

The Board helps those that help themselves.

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Koshchi wrote:
About the only thing that you need to use the R/W line for is detecting when the LCD has finished the previous command. Most people just use hard-coded delays instead.

all of the libraries I have used, use the rw line. Do you know any libraries that don't use it / is it relatively simple to recode it for use with out RW?

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Sometimes, the READ/write line is set to READ:Elektors board for the book http://www.elektor.de/products/b... (with samples of code, using delays; exists in Dutsh, French but did not find in Englis) is in this case (I suppose the READ is "only" used to wait for the LCd to be ready instead of waiting some time).
Are there many primitive, lowlevel functions in a LCd library (ie : init, clear, put a character somewhere and many other I forgot -not converting a digit into a char, really low level functions)?

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Perfect, thanks Peter.