Help !! - Interfacing lcd with arduino using 8255A Intel peripherals

Using Arduino Programming Questions
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Hi Guys,

I'm new to all this stuff and for two past days, i have been trying to interfacing an LCD 16x2 crystal screen to arduino UNO using an Intel's peripherals 8255A component without any luck. the problem is how can i attach or set the LCD's pins <<LiquidCrystal lcd(12, 11, 5, 4, 3, 2)>> to the unknowing pins from 8255A.

Is it even possible?

thanks for any kind of help.

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You can't use the built-in LCD library to talk to an LCD on the far side of an 8255A Peripheral Controller. You will have to write your own LCD library, probably starting with a copy of the existing library.

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Thanks Mr. john wasser for you receiving me, but i would be more than happy if you can give some more details about this solution, and how can i use and edit the build inside the LCD library.

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Hamza_TST:
how can i use and edit the build inside the LCD library.

Find the folder containing the built-in LCD library. Copy that folder to the 'libraries' folder inside your sketchbook folder. Change the folder name and file names so the two libraries don't have the same name. Every place where the library accesses any pin connected to the LCD you will have to change the code to do the access through the 8255A Peripheral Controller.

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This is my problem mr. john, i tried to do that but it dosent work for me at all, i would be very very grateful for your help mr John if you do that on behalf of me (just the new LCD library) and you have already the 6 needed pins for my ciruit.

Thank you.

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It would be very hard for me to design and write the code without having the hardware to run it on.

If you would like me to attempt to re-write the LCD library my rate is $US20 per hour. Five hour minimum ($100) in advance. I expect it to take about 20 hours ($400) total. You might find someone local or someone willing to do the work for less if you post under "Gigs and Collaboration".

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Hi,
Wouldn't you be better off going to a controller like a MEGA that has more output pins and you can drive the LCD from a separate set of pins to the 8255A.
In fact will the MEGA have enough I/O that you would not need the 8255A.
You wold have to check that any libraries you are using would work okay on the MEGA.

Hope that helps.. Tom... :slight_smile:

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TomGeorge:
Hi,
Wouldn't you be better off going to a controller like a MEGA that has more output pins and you can drive the LCD from a separate set of pins to the 8255A.

I do agree, but would that not take the fun away :slight_smile: An I2C LCD and a I2C port expander for the 7 segment display might also be a possibility.

Hamza_TST:
Hi Guys,

I'm new to all this stuff and for two past days, i have been trying to interfacing an LCD 16x2 crystal screen to arduino UNO using an Intel's peripherals 8255A component without any luck. the problem is how can i attach or set the LCD's pins <<LiquidCrystal lcd(12, 11, 5, 4, 3, 2)>> to the unknowing pins from 8255A.

Is it even possible?

thanks for any kind of help.

A note on your schematic: if the serial port of the Arduino is used for communication over RS232, you need level converters like the MAX232 (or similar). Guessing you're reviving old PC hardware, have a look for them or the 1488/1489.

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haha yeah of course mr. sterretje i'm agree with you, and this is probably what i'm gonna to do :slight_smile:
thanks TomGeorge for your advice, i will use the MCP23017 instead the intel's 8255A component

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