View Full Version : Need suggestion for TFT LCD interface.

09-06-2007, 06:22 AM
I have been tearing apart the Spin examples from the site and am learning a lot pretty quickly. I have some code that Ive been messing with for a few days and getting some pretty exciting things from the 2.5" Parallax TFT LCD screen through the TV.spin object. I need to find a 1.5" to 1.8" screen that I can mount in my own case. There are plenty out there but im unsure of the interface to get because most of them do not take composite video. I am new to the video stuff and dont really know what to get. Do these things use serial natively or is it something different all together. Do they use VGA meaning I have to re-write my code? I'd like to get more colorful with the display and should have the Hydra book tomorrow, so hopefully that helps. Any suggestions?



09-06-2007, 06:46 AM
Im finding things like...

MPU interface mode: 8080/8-bit
LCD controller: HX8310 or equivalent

Interface: parallel 8080 or 8088

LCD controller: NT7525

http://forums.parallax.com/images/smilies/shakehead.gifˇGreek to me.

09-06-2007, 02:01 PM
Reading the first 200 pages of the Hydra book will give you a lot of enlightenment!

09-07-2007, 12:04 AM
So, it looks like the 8080, 8 bit interfaces are probably the way to go? From what I gather from the Hydra book, the VGA mode uses an 8 bit parallel output mode.

09-07-2007, 12:26 AM
Scoupe, I do not want to sound unhelpful, but it would be a very long story to tell. I seriously should suggest you start wtrh something simpler and come back to your CRT project a little bit later.....

The reference to 8080 and 8088 will say that you have to simulate the bus protocol for that processors, which is not difficult, but is not what the video logic of the propeller generates.

You need not only 8 data bits but also 3 control lines and most likely 10 to 12 address lines, assuming those displays contain an own video memory. This all can of course be done by simple OUTA instructions....

Post Edited (deSilva) : 9/6/2007 5:59:58 PM GMT

09-07-2007, 12:46 AM
I dont see you as being unhelpful. I see it as straight forward and honest. :) Not really having more time to spend on the video aspect of this than I do the actual program coding, Ill stick with composite video for now. Looking at this Hydra for for the past 2 hours has amazed me even more with the possibilities of this chip. Simply amazing!

09-07-2007, 01:02 AM
The chip IS amazing. A minor problem is that some people want to prove you can do EVERYTHING with it. This is really not necessary because Alan Turing has already done this 70 years ago.

But some things can be accomplished more easily than others http://forums.parallax.com/images/smilies/smile.gif

09-07-2007, 02:38 AM
Agree DiSilva the chip design is the best alround embedded chip design on the market these days. As you mentioned don't expect a NVIDIA look like thing for the video but nevertheless I give a great complement to all the engineers worked on this project. They tried to build a multifuntional multicore low power chip and they succeeded very well in the objective. ( even intel has only 4 cores at the moment http://forums.parallax.com/images/smilies/wink.gif

I can assure you that if you want to accomplish the same multifunctional project using a eg ARM7/9 core you easly get a very complex system. The power consumption will be 5 to 10 times higher than the propeller (6mA average / cog )

If the engineers increments the amount of memory in the future the propeller chip can break through in many applications.

Indeed also me i'm new in this and I quickly had a great feeling in playing with the existing good driver code this also speed up the development of new object hugely. You take an object compile it and of you go. this can't be always said of other core architectures in respect to community exchanges !

The cream on the cake is it's all for free ! A special thanks to the people who build wonderfull object ready to use out of the box.


I'm NOT a PR agent of Parallax http://forums.parallax.com/images/smilies/wink.gif