topic 16-color, 4bpp using custom palette under emwin in LPC Microcontrollers

16-color, 4bpp using custom palette under emwin

lpcware — Wed, 15 Jun 2016 17:16:21 GMT

Content originally posted in LPCWare by wendtr on Fri Apr 19 16:45:04 MST 2013

I am intending on running emWin using built in RAM only. I do not want to use more than half of the built in RAM for display buffering, and our application allows us to run the display using a fixed, custom 16-color palette (which can be themed) using 4bpp mappings. This would utilize roughly 35K of RAM for a 320x240 LCD. Is there an example of the code required to set this up? I am pretty sure the LPC1788 supports this mode.

Re: 16-color, 4bpp using custom palette under emwin

lpcware — Wed, 15 Jun 2016 17:16:22 GMT

Content originally posted in LPCWare by wmues on Mon Apr 22 04:46:08 MST 2013

The LCP1788 LCD controller is very easy to set up. Just look in the manual and setup the register.

But: if you want to change the display contents without visible screen disturbance, you have to use 2 RAM buffers. So I think your approch of using only internal RAM will not work.

Re: 16-color, 4bpp using custom palette under emwin

lpcware — Wed, 15 Jun 2016 17:16:22 GMT

Content originally posted in LPCWare by wendtr on Tue Apr 23 17:54:18 MST 2013

I was hoping to avoid having to write a from-scratch c-program, and leverage emwin for this application. What I could not determine from the emWin documentation is how to establish a custom pallete to work with a 4bpp drive. I think its about initializing emWin properly.

Re: 16-color, 4bpp using custom palette under emwin

lpcware — Wed, 15 Jun 2016 17:16:23 GMT

Content originally posted in LPCWare by wendtr on Tue Apr 23 17:54:42 MST 2013