CFA-633 Displaying Special Characters


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I see in the data sheet for CFA-633 how to store special characters (command 9) to CGRAM. I could not find any reference on how to display the special characters for instance in a "send data to LCD" command. I am also presuming that to get the characters in the CGROM map, one would use the reference given in the character map ie b00010011 for the number 1.

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CF Tech

The CGRAM characters appear in location 0 to 7 (and are aliased at locations 8 to 15) of the character map. So just send out 0 to show the first custom character, 1 to display the second . . .


USB LCD Displays - Graphic and Character LCDs with a Keypad


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C example of special character

I see the documentation on where cgram is and what type etc, but I'm still too dense I guess to make it happen in my C app...

Anyone have a short snip that shows me how to define a cgram character and how to send it to the lcd (633)
Last edited:


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Here's what I'm doing in a nutshell, and it isn't working. The last part, where it sends the character, is producing a glyph on the LCD, but the first part, where I'm trying to change the CGRAM, isn't working. This code is leveraging the cf_linux_examples.tgz that is being distributed with the CFA-634.

unsigned char CGRAM128_STRING[10] = { 25, 128, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x3F };
char str[20];
//First turn off "scroll" and "wrap"

SendData(CGRAM128_STRING, 10);
sprintf(str,"%c", 128);

The link provided for the utilities is leading to tools to make 5x7 rather than 6x8 glyphs, by the way.