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CFAX1286 - mode and parallel code


New member
Three questions about the CFAX1286

1. My interface is a 3.3V system (MSP430). Does the C86 line, selected for 6800, establish a 3.3V interface (versus a 5V) or does this line have another purpose? If another purpose, which is the best C86 mode to use for writing control/character data (only) to the display?

2. Are there any examples available for driving this LCD in parallel? All the examples I can find use a serial bus.

3. If using serial, apparently the serial bus is SPI, yet there is no separate MISO line. Does one ignore Master In Slave Out? Also, what should STE (Transmit control enable) be connected to on the LCD?
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Three questions about the CFAX1286
There is no "CFAX1286", so I'll assume you mean CFAX12864, of which there are a number of variants. I used this display eons ago, so I have some familiarity with it. Your questions:

1. Its always 3.3V, there is no 5V mode. The C86 line chooses between "6800" and "8600" types of CPUs. This basicly controls the interpretation of the "E" and "W/R" lines, for clocking in the data. If you are writing your own code, there is no advantage to 6800 mode over 8600 mode.

2. I guess you would want samples in C code. To give good answers, I would need to know which display model # you are referring to. In reallity, the parallel bus driver code is extremely similar for most all low-level graphics displays. I only have Motorola style (6800) assembly code for this particular display. But I could give you some C code for other graphic displays that would be easy to adapt.

3. I think its not standard SPI, as I believe these displays are "write only"; no return data is sent. To understand what the STE signal means, I'd need a real model #.


New member
Thank you.

The exact model is the CFAX12864U1-TFH

Thanks for clearing up the 8080/6800 confusion.

Yes, would very much appreciate some examples written in C of driving this display in 8 bit parallel mode.

I am attaching 2 assembler files that I used to drive this display (actually a previous version that used an earlier controller chip). The purpose of these files is to show the commands and data used to initialize the display.

This link is for zipped C code for a color graphic display that uses virtually the same bus protocol, but has command and data that are for a controller thats not compatile with the CFAX. Clicking the link executes a script that should initiate a download.

You can extract these 2 files:

The code in the C file(s) performs the same functions as the assembler code.

When you have looked at these files, we can discuss how to adapt it to your CPU environment.

If you want some background on my code samples, and my font editor, you can browse here:



New member
Thank you!

What you provide here is an excellent start.

The font editor looks promising, too.

All the best,