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cembeddedlcdinverse

LCD inverse text (CV12864C & RA6963 controller)

I am trying to figure out how to display inverse text (black BG, white text) on a Clover CV12864C LCD display which uses a RAIO6963 controller (or similar).

I can do pretty much everything I need however inverse text is stumping me.

The spec sheets are here:

http://www.cloverdisplay.com/pdf/CV12864C.pdf http://www.mitsutech.com/RA6963_DS_v13_Eng.pdf

So I can see I need to do the following:

  1. Set mode to Text Attribute 0x84
  2. Set Display mode to Text on, graphic on 0x9C
  3. Set attribute function to 0x05 (but how do I do this?)

I can't see in the spec sheet what command to send to the LCD to do this. Is it as simple as sending 0x05 (i dont think so).

Help appreciated, help with code super appreciated. I am working in C.

Solution

  • After a short look at the datasheet of the controller, I'd say that:

    • You must enable text and graphics mode.
    • enable text attribute mode
    • Graphics mode will not be available (page 24ff).
    • Write text attributes to graphics memory area, text to text area
    • as for text: one byte per text symbol
    • Text-address and attribute (graphics) address correspond
    • So you must use both address pointers and setup all related registers accordingly.

    So, the attribute for text symbol at address 0 would be in graphics memory area address 0, ...

    Alternatively you can set the whole display to reverse. That might work for text and graphics.

    Nice features, but that chips is quite a bit outdated, as it requires apparently some other chips around. More recent COG (chip on glass) panels use just one chip for driver/dc-dc converter/refresh (incl. memory) and CPU interface. But thy only have graphics (no big loss actually).