TFT issue

Mailar · Joined: 21 Sep 2010 Posts: 3 Location: Bangalore

Hi, We are trying to interface a 10.4" tft lcd module with touch panel to a pic micro-controller. Here our aim is to read Picture source from USB using PIC and displaying it on TFT via LVDS convertor. Here we dont have problem with USB side, but the issue is on interfacing. So, we want know how would be the interfacing and data transfer between PIC and and TFT via LVDS converter.

and here are the links for data sheet and Block diagram for more details.

http://www.flickr.com/photos/55068707@N02/5106959612/#/photos/55068707@N02/5106959612/lightbox/

http://www.datasheetcatalog.org/datasheet/texasinstruments/sn65lvds105.pdf
http://tianma-europe.com/downloads/tm104sbh01_f_v2.1.pdf

another issue is that, we are using sn65lvds104/DS90LV047A LVDS converter is that suitable for tm104sbh01 TFT ?

if any body knows or any other documents available except datasheet pls suggest me...

thanks allot...

Douglas Kennedy · Joined: 07 Sep 2003 Posts: 755 Location: Florida

When working with LCD screens the first thing many do is to calc the pixel refresh rate. If the LCD doesn't have a controller with memory then the PIC device has to do the task of refreshing the pixels . Ex the lcd is 640x480 pixels. The pic can execute an outport instruction to send 8 bits every 4 clocks. The screen will flicker at say 80 hz. So we need 640x480x80/8 bytes per sec or3,072,000 now say the pic is clocked at 40mhz that's 10million bytes per sec. That leaves 3 other instructions to fetch the data before outputing it. This very rough calc shows the pic can't act as a controller and refresh the pixels. You need a panel with built in video ram and a controller.
Otherwise you have to roll your own. FPGA's are a solution but you have to know how to program them VHDL ABEL Verilog. The LVDS is an interface it is not a controller so if the LCD lacks a controller the pixels still need refreshing.