marlin firmware and half height prints

[printbus]

I think there was code posted... But one of our members here knows all about the LCD Panel corruption and how to work around it. If you search for i^2c you will find where I got corrected on how the panels work and the code (and explanation) that you want.

Roxy - I could have elaborated, but I was wondering about the changes specific to the half-height problem. As to the display issue, the OP is trying to add a graphic display panel onto his printer, not one of the usual 20 characters by 4 rows jobs. I have no idea whether the graphic panels use the same nibble interface that the character displays do, but I'm guessing the interface could be quite different. I'm actually the one who explained the character corruption issue we can get on the 20x4 displays, but it's not related to the OP's display issue. FWIW, the thread where I discuss the 20x4 screen corruption problem is in the firmware enhancements to marlin area - http://3dprintboard.com/showthread.p...ed-LCD-screens

FOLLOWUP COMMENT: The pixel mapped graphic display modules don't have the nibble transfer mode, so the nibble-sync issue that leads to corrupted text on the 20x4 LCD modules shouldn't be possible. Marlin communicates with the graphic module using Serial Peripheral Interface (SPI), like it does with the SD card.