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Scrolling for CFAF240320K-T-TS


New member
How can you make the display scroll? Are there any special settings needed?

The display now works perfectly, but I can't get it scrolling. The code I have is in SPIN, but you should see what I do:

repeat y from 0 to 319
lcd.exec1( lcd#CMD_CMDOUT, $6a00)
lcd.exec1( lcd#CMD_DATAOUT, 2<<8 )

waitcnt( clkfreq/100+cnt )

I send $006a as a command followed by $0002. (LSB and MSB are reversed in the code above for easier handling in the propellers assembler). Shouldn't the display scroll up 2 lines then?
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New member
Hmm ... this forum seems to be not very helpful. I'd suggest to discontinue, as it's better to have no forum than one where nobody takes care of from your staff if nobody else can help.
Maybe you should rather think of using a Wiki instead, into which you put your knowledge and the outcome of the FAQs.

CF Support

The problem lies in the fact that you haven't enabled scrolling function in your initialization. Per the SPFD5408B controller datasheet, which you can download from here:


or directly:


Page 35 states:

VLE: SPFD5408B provides vertical scrolling function which can be
set by VLE bit.
VLE = “1”, vertical scrolling function enable. The amount of
scrolling line from the first line is determined by VL[8:0].
Directly following on the same page is the Vertical Scroll Control register described.

Hope that helps.


New member
"And in the end everything will be good ;o)"

I suppose you are right and that's the problem.

Please apologize my last post, but I compare this forum with the forum that parallax runs - which is much more responsive on any question. Mostly because the forum users stay and help. I think your problem is that users dissappear as fast as they appear and there is less help from user to user.

Is there a big difference in the CFAF240320 and the 3,5" display? I mean in programming. Or can I take the driver I wrote for the display and use it on the other one? Now that I know of the capabilities of the 8 bit bus I plan to switch to a display which provides the 18 bit bus.

To be hones I'd like to have a display that's even bigger than 3,5". Will there ever be a bigger display that already includes a controller with it's own display RAM?