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LCD Read/Write operation

jab99407

Member
I am looking help to understand datasheet of 16*2 LCD. Please look at this datasheet http://www.picaxe.com/docs/led008.pdf

Page 3 Timing char, I do not understand read and write operation there are three control signals RS, R/W and E

if I want to send one byte to LCD display How these three signals work for read and write operations ?
 

DrG

Active Member
I am looking help to understand datasheet of 16*2 LCD. Please look at this datasheet http://www.picaxe.com/docs/led008.pdf

Page 3 Timing char, I do not understand read and write operation there are three control signals RS, R/W and E

if I want to send one byte to LCD display How these three signals work for read and write operations ?
The three signals work just as in the diagram, but remember that RS (Register Select) will determine whether what is read or written is a register or data.

if I want to send one byte to LCD display How these three signals work for read and write operations ?
Look at the table on Page 6. See the state of RS and R/W for different actions?
 

jab99407

Member
Are you using a picaxe controller?? How many pins? are you connecting 2 control and 4 data?

The normal way with the picaxe is serially using an LCD backpack
No, I had to find out how we send data to the LCD So i looked at the datasheet But I do not understand what should I do if I want to send one byte data to LCD


Table can help me to understand read and write operation 16*2 LCD

Control signalsWrite operationRead Operation
RS??
RW??
E??
 

DrG

Active Member
No, I had to find out how we send data to the LCD So i looked at the datasheet But I do not understand what should I do if I want to send one byte data to LCD
I think you need a little better understanding of what sending a byte of data to the controller means. The Table on page 6, which I referenced, explains it - but you may not know enough background to understand that.

Two papers were suggested in a previous post: They are linked below. Reading through those may help.
 

jab99407

Member
so I this is sequence to write command or data to lcd
/*LCD 8 bit example
rs => Register Select [Command : Data]
0 => Command
1 => Data Set RS high for Data.
rw => Read/Write [Write : Read]
0 => Write
1 => Read
en => Enable signal [High to Low]
 

Pommie

Well-Known Member
Most Helpful Member
That is the right sequence but the display has to be properly initialized as explained in the datasheet or it won't do anything.

Mike.
 

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