Firmware improvements


New member
Hey Brent,

I was recently playing with the marquee option on the 634 (fw version 1.3), and have a couple of suggestions for future revisions of the software.

Would CrystalFontz consider making the max string length for the marquee message more than 20 characters, as it is right now?
I wanted to use the marquee function to overcome the 20 character width constraint on the LCD, and was a bit surprised to read that it supported no more characters than a static line. I realize this would require more memory than the current 4x20 display buffer, but this would be an awesome addition to make.

Also, it'd be nice if the first 20 characters of the marquee text were displayed when the marquee was turned on (maybe with a variable delay before scrolling?). Right now, the line starts off as blank, then the text scrolls R->L. Especially in an MP3 player context, it's nice to see the song name briefly at the start of the scroll.

Thanks for listening, and keep up the great work!

--- Rupert

Rupert Scammell
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CF Tech


Thank you for your suggestions. The processor we are using is quite limited on memory, and in the first version of the firmware there were just over 20 bytes left, so we wrote the marquee function to use them up.;)

Seriously, though I think the current display can do what you would like. The characters that are rotated through on the 634 are the line (20 characters) and the buffer (an additional 20 characters), making a composite circular buffer of 40 total characters.

The trick is to set up the first 20 characters of your message on the line that will be scrolling, and the next 20 in the buffer. Then when you enable scrolling the entire group of 40 characters will scroll by. It does look best if you leave about 5 or so spaces between the start an end so there is a visual break, but it is not required.

Did you try playing with the WinTest program? It has a window that lets you play around with the scrolling buffer: