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CFA635: Program boot state w/o displaying it


New member
I'd like to be able to program a message for boot-up (using command 4) without showing the message on the display, even briefly, while programming it. (Basically, I'd be doing an internal flash reprogram which, if interrupted, will prevent me from accessing the CFA until the flashing is repeated successfully. I want to put a message that will be displayed if the box is power-cycled.)

Obviously, I cannot do something like turn down the contrast to zero since that will be saved in the boot state. Is there some way to maybe temporarily power-off the display itself without saving that as part of the boot state? Maybe a command to the controller through command 22?

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CF Tech

You could try sending a display off to the LCD controller, but when command 4 executes it reads the display memory out of the LCD controller. If that reads back OK even with the controller off, then it might work.