Help swapping out LCD on A6

Hi All, I have an Anet A6 that the LCD has been getting darker and darker until now, full dark. I have a 20x4-LCD board with encoder that came from another older printer with dual ribbon cable connections, EXP1 and EXP2.

I set Marlin 1.1.9 for REPRAP_DISCOUNT_SMART_LCD bu get a compile error, "no pins defined."

I tried using the same LCD definition (ZONELABS) as the Anet A8 which has the the 20x4 screen and it compiles and uploads, but I only get a back-light.

How can I regain control of the A6 with the 20x4 without buying a new full-graphics module?

The other upside is that I should then be able to un-define SLIM_MENUS"

Thanks

Edited 1 time(s). Last edit at 01/16/2019 10:33AM by StlLooking.

From the file pins_ANET_10.h

/**
* LCD / Controller
*
* Only the following displays are supported:
* ZONESTAR_LCD
* ANET_FULL_GRAPHICS_LCD
* REPRAP_DISCOUNT_FULL_GRAPHIC_SMART_CONTROLLER
*/


Your controller doesn't have enough free IO pins for a standard 20x4 (it uses more pins than all the rest)

Thanks, but the A8 uses what looks to be the same board and it has enough pins for the 20x4. In my OP "ZONELABS," I meant "ZONESTAR" as you mentioned.

>> Your controller doesn't have enough free IO pins for a standard 20x4 (it uses more pins than all the rest)

This would suggest otherwise when making the reverse happen...
[www.thingiverse.com]

the A8 does use the same board

The zonestar 20x4 lcd is different as it only uses 1 analog pin for the 5 buttons
the standard 2004 lcd uses 3 digital pins for the encoder and switch.

the 12864 lcd also uses less io pins than a standard 2004 lcd, it uses spi for the lcd vs 4 bit parallel

the 2004 needs
lcd: 6 io lines
buzzer: 1 io lines
encoder: 3 io lines
SD: 5 io lines (must include SPI pins)
reset: 1 io line
Total: 16 io lines (if you use it all)

the A6/A8 has
4 SPI pins on J3
8 pin on LCD
Total 12 pins.

Quote
Dust
the standard 2004 lcd uses 3 digital pins for the encoder and switch.

Ahh, OK, thanks for the detailed explanation, it is very much appreciated. As you can tell, I am quite a way out of my depth with this. I was reading on the Repetier site that the Graphics screen can take 0.1 to refresh and slow down Deltas, so I figured I would go back to the 20x4 o the A6 to get the expanded menu options and give the board some breathing room in speed as a bonus. But, that is not to be.