Paul Staron

Important changes to forums and questions

All forums and questions are now archived. To start a new conversation or read the latest updates go to forums.mbed.com.

9 years, 4 months ago.

Larger display problem

Using the Wonder Geko, works fine resizing to a smaller pixel display (96 x 96), however the 400(w) x 240(h) display will not print text (or graphics). The display will clear but only prints a small line of pixels across the top right corner.

Updated to the latest libraries (both platform and LCD) and does resize the RAM buffer usage, to around 18k on the larger display as expected.

I have used this display library (with some modifications) on this platform that works on both display sizes, but this has no low power asynchronous mode.

https://developer.mbed.org/users/rgrover1/code/SharpLCD/

Any suggestions?

Question relating to:

Last updated: 12 Aug 2015
Display driver for Sharp's range of SPI-driven memory LCD's, leveraging the power of asynchronous transfers. Currently supports LS013B7DH03, but easily extendable to other models as well. async, LS013B7DH03, memory lcd, Sharp, sharp memory LCD

Hi Paul,

I sadly don't have access to this specific kind of display, and so debugging the issue becomes kind of complicated. Do you possibly have access to a logic analyzer to see if the problem is in the data transmission, in the display timing or in the framebuffer? I will try to initialize the code for the size you mentioned and do some analyzing on it.

posted by Steven Cooreman 21 Jul 2015

1 Answer

Steven Cooreman
9 years, 4 months ago.

Hi Paul,

can you change the definition of 'DISPLAY_BUFFER_TYPE' in LCDSettings.h to uint8_t instead of uint32_t? Because the display size you are trying to drive is no integer multiple of 32, some of the calculations inside of the library will return a floored result, which in turn causes the library to fail.

On my logic analyzer capture, the output on Wonder Gecko looks okay after that change.

That worked, also checked with the 128 x128 and 96 x 96 display modules. There is an issue with the showBMP that I have adjusted and now works:

/media/uploads/star297/20150721_172423.jpg

Still 8 bit aligned, so can't place to pixel precision but does work, do you want the changes?

posted by Paul Staron 21 Jul 2015

Yes, please! :)

posted by Steven Cooreman 22 Jul 2015