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Why lcd controller is so important?

Started by Unknown April 2, 2009
I want to implement a monochromatic graphic display with an 8 bit
micro....this display requires clock frequency of 10MHz max, and my
micro is used at 16MHz...Is impossible to drive this display without
any controller?What do you think?
Thanks
silusilusilu@gmail.com wrote:
> I want to implement a monochromatic graphic display with an 8 bit > micro....this display requires clock frequency of 10MHz max, and my > micro is used at 16MHz...Is impossible to drive this display without > any controller?
Pretty much so, yes. For starters, a CPU running off a single 16 MHz clock can't even generate a 10 MHz clock signal, much less output controllable data at that rate. You don't necessarily need a specialized LCD controller, but you will need some device that the CPU can offload the LCD data refresh to. Either that, or a *much* faster CPU.
silusilusilu@gmail.com wrote:
> I want to implement a monochromatic graphic display with an 8 bit > micro....this display requires clock frequency of 10MHz max, and my > micro is used at 16MHz...Is impossible to drive this display without > any controller?What do you think? > Thanks
If you think of an LCD glass like a CRT, then can you display on a CRT without a controller ? Yes you can, but it will require timing signals to be constantly driven but the microprocessor. Same problem with LCD glass, someone has got to do it, its usually easer to do it with a controller. good luck don
silusilusilu@gmail.com wrote:
> I want to implement a monochromatic graphic display with an 8 bit > micro....this display requires clock frequency of 10MHz max, and my > micro is used at 16MHz...Is impossible to drive this display without > any controller?What do you think? > Thanks
Hi! Here are some examples: Howto on generating video signals using PIC. (Written by me): http://www.rickard.gunee.com/projects/video/pic/howto.php VIDEO TETRIS: A video game with software generated video signal ! http://www.rickard.gunee.com/projects/video/pic/tetris.php http://www.web-ee.com/Schematics/PICTetris/PICTetris.htm http://www.rickard.gunee.com/projects/video/pic/tetris.php PIC Breakout: http://www.acm.uiuc.edu/sigarch/projects/breakout/ http://www.acm.uiuc.edu/sigarch/projects/breakout/breakout.asm PIC-Tock: http://www.brouhaha.com/~eric/pic/pictock.html PIC-Pong: http://www.brouhaha.com/~eric/pic/picpong.html VCR Pong: http://dt.prohosting.com/pic/pong.html Alien Slaughter! A Video Game Computer based on 3 Microcontrollers: http://www.ugrad.physics.mcgill.ca/~beek/alienslaughter/ Video Clock Superimposer: http://dt.prohosting.com/pic/vidclock.html http://dt.prohosting.com/pic/vid_src.txt http://dt.prohosting.com/pic/vidclock.gif Glenn
On Apr 1, 11:25=A0pm, silusilus...@gmail.com wrote:
> I want to implement a monochromatic graphic display with an 8 bit > micro....this display requires clock frequency of 10MHz max, and my > micro is used at 16MHz...Is impossible to drive this display without > any controller?What do you think? > Thanks
Yes, most LCD panel accepts 1 bit or 4 bits data stream. But you need a big video buffer (16K to 32K Sram) and logic to serialize it at a constant rate.
Glenn M�ller-Holst wrote:
> silusilusilu@gmail.com wrote: >> I want to implement a monochromatic graphic display with an 8 bit >> micro....this display requires clock frequency of 10MHz max, and my >> micro is used at 16MHz...Is impossible to drive this display without >> any controller?What do you think? >> Thanks > >
By the way - the technique is called bit-banging and is a quite common in smaller embedded systems: http://en.wikipedia.org/wiki/Bit-banging It can be used to generate and interpret many forms of signals. The best in terms of power and to minimize mips is to use a dedicated hardware subsystem. Glenn