21 thoughts on “RA8875 – Custom Font PDF

    1. Its in the lcd code .. thats normal stuff…

      ////////////////Text write position
      void FontWrite_Position(uint X,uint Y)
          unsigned char temp;


  1. I must be thick… If I want to render the letter “A” in my custom font (assuming I already created the bitmap for “A” in my C code) at position 221x 115y, what would the code sequence look like?

    Load_Char(0, myCustomAArray);
    FontWrite_Position(221, 115);
    // how do I tell it to actually draw the loaded font charter here?

  2. Hah i guess i should add that to the PDF… ASCII is simple enough most drawable characters are from 32 to 126 aka SPACE to ~ …

    To make it simple you can draw the letter A (capital) in its position which is 65.


    Write_Dir(0x40,0x80);//Set the character mode
    Write_Dir(0x21,0x80);//Select the internal CGRAM


    If you are just loading a symbol such as the BATTERY symbol then keeping it in place doesnt matter. So you can start at 0 like:


    Write_Dir(0x40,0x80);//Set the character mode
    Write_Dir(0x21,0x80);//Select the internal CGRAM


  3. You rock! This is exactly what I was looking for.

    Last one – font size/scale. By default, they’re 8×16. What if I wanted 2x, 3x, etc? I thinks there’s another LCD command for this, or would/could we define a larger custom font array?

    1. Thats what i plan to look into next. I have some 16×16 fonts i would love to try. There are only 255 spots in the font available so larger fonts will be shortened to less characters.

      I updated the PDF and im glad this helped!

  4. Was looking at your git code again, and I don’t see where you actually draw your buttons on the LCD. I see the Init code that sets position, but don’t see where you actually draw them? Are you just rendering one big static BMP and then mapping touch locations that correspond with areas in the BMP?

    1. I actually do both. The volume and channels are drawn individually as they have 3 states. The other buttons are 1 large image and individual sections are drawn based on touch. Check the ta8875.c file for openasi.. asi is my own custom file type

        1. possibly if the image is tiny. Im using SPI for SD also so i have to deselect the chip and im not sure if it looses that state. So i just resend it.

    1. I havent used this with Arduino, sorry. But it shouldnt be to hard to implement it. The code should be almost copy and paste-able. Do you have arduino code made for the LCD already? I can add my code to it for you.

    1. Hey buddy! I got the screen from : http://www.buydisplay.com/default/7-inch-lcd-module-capacitive-touch-screen-panel-i2c-spi-serial.html

      It uses SPI/I2C/Parallel interface, Depends on which one you use. If SPI.. Then 4 SPI lines… If you get the Capacitive Touch version like me then you will also need I2C for the touch screen. It doesnt use 40-50 lines.

      Check this out: (MCU they chose is the STC12LE5A60S2)

      Click to access ER-TFTM070-5_Interfacing.pdf

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: