extending alpha numeric ic

[raman00084]

i am having 20 x 4 alpha numeric display i want to extend 5mts from micro controller board how can i do this

my lcd have the following pins
rs,rw,en,d4,d5,d6,d7( 4 bit mode)

my idea is converting micro controller output to differential using am26ls31 and then converting it to single point by using am26ls32 will this work for 5mts length without any noise?

are give some idea to do this without noise



regards
kalyan

 

[xenos]

Of course you could use differencial receivers/transmitters.
I think 26ls31/32 are obsolete.
Have you tried shielded cable and failed?
RC filters could be useful also in lines (especialy ENABLE signal).

 

[raman00084]

how to connect the rc filter you mean low pass filter, what value of r and c can i use

 

[xenos]

Low pass first order RC filter with 1nF and 1KΩ resistor for cutoff frequency of about 200Hz.
You still need shielded cable to eliminate relay triggering and other high power low frequency distarbances.

 

[raman00084]

you mean 200khz?

 

[KlausST]

Hi,

another way could be to use LVDS serdes transceiver.

It´s like parallel in - serdes - parallel out. But the serdes communicates with one differential pair (for a lot of parallel lines).

**
or displays with SPI, UART, RS232, RS485 interface...

Mind to include ESD protection.

Klaus