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Posted: Sun Mar 16, 2008 5:14 pm
I'll do my best but it will take time. That is not a simple task as you've no doubt found out.
Since it is for your senior project I suggest going through what you have working and finding where the difficultly is in changing the code for 20 MHz. It's best that you can explain and understand what problems you ran into while creating a project.
So please be patient and I'll see what I can get working.
Posted: Tue Mar 18, 2008 11:23 am
I'm not sure about the schematic attached to the project.
It seems to mismatch the assembler code.
As reading the code, it seems that we should have :
RED PORTB, 0
GREEN PORTB, 1
BLUE PORTB, 2
HSYNC PORTB, 3
VSYNC PORTB, 4
But on the schematic, man can read:
RED PORTC, 2
GREEN PORTC, 2
BLUE PORTC, 2
HSYNC PORTD, 0
VSYNC PORTD, 1
The best is to follow the code isn't it?
Posted: Tue Mar 18, 2008 5:09 pm
Yea I messed up on the schematic, I've been meaning to change it.
You can change the code if you want, it will work either way.
Sorry about the mix up.
Posted: Mon Mar 24, 2008 2:11 pm
what happens to 20 MHz code that we told you about??? plz we want your help very much ,,,, waiting your reply
Posted: Mon Mar 24, 2008 4:49 pm
I'm working on it. Last week was holiday for me.
I should have some example code that works in 2 days.
I'll send you an e-mail with the code when I have something for you.
Posted: Wed Mar 26, 2008 3:16 am
I managed to get some 'semi-working' code for you to look at.
My resources are limited so I wasn't able to test it out on a CRT monitor. It displays momentarily on the LCD's so I'm sure some
output will display better if you can test it out on a CRT monitor.
Here's the code:
http://www.pyroelectro.com/projects/vga ... hz_vga.asm
It displays Black for the first 240 lines and displays Red for the last 240 lines.
I'll see if I can test it on a CRT tomorrow, maybe.
Posted: Wed Mar 26, 2008 5:53 pm
Im looking for a device that can send a complete white and complete black screen to a VGA - LCD monitor, i think i found it
I can program PIC's over here.
But my question is how the code must changed?
Posted: Wed Mar 26, 2008 6:23 pm
In order to send a white color signal all 3 colors on the VGA cable; Red, Green & Blue must be set for maximum intensity. Kind of like in paint programs where if you set Red, Green & Blue to 255, 255 & 255 the resulting color is white.
It may be tricky to do it with the PIC method. Tomorrow I will be posting another method for creating VGA signals that is more reliable and only a little more complex than the PIC method, it will use VHDL.
So check out the site tomorrow!
Posted: Tue Apr 08, 2008 3:50 pm
Can you find to us a good application using vga other than VGA TEST BOX?????
thank you for your help to us
Posted: Tue Apr 08, 2008 8:18 pm
I answered that question here:
Feel free to reply to it there.
Posted: Wed Apr 23, 2008 11:30 pm
what is the monitor type and number that you worked on it??????
plz write it to me
best regards to you
Posted: Fri Apr 25, 2008 12:06 am
I used it on a generic Dell 17 inch monitor as well as on many other generic VGA-CRT monitors. It worked just fine on most all the crt's.
Posted: Mon May 12, 2008 6:56 pm
Hello agian, its been a while.. I have started my project and am having some issues...
Just to make sure I get something, I have hooked 3 freq. gen. to the H-sync, V-sync, and the blue pin. Set H to 31KHz, set V to 60Hz and any signal for the Blue... I get a blue streeks on the screen, but the screen flicks on and off. Is there any problem if the frequency of H & V are not exact.
Second, with the frequency of the H & V set, i tried to connect my chip to only to the blue, I wanted to handle just the screen output and no sync...
I dont get anything on the screen. Does the colors have to be off durring the blanking times?
Posted: Tue May 13, 2008 1:15 am
Blue streaks across the screen is good news, it means you're getting some where. The flickering off and on means that the screen doesn't like one of your inputs: V-Sync, H-Sync or Color.
If H-Sync or V-Sync aren't exact problems can occur. The reason this tutorial was created using a CRT is because CRTs are more forgiving to signals that aren't exact.
Ideally the color R,G,B should be off during blanking times so the CRT doesn't get confused but it should still work as long as your H-Sync & V-Sync are correct.
There's a bit of guess and check work necessary once you get the signal delays around the properly specified values.
Posted: Sat Jun 28, 2008 4:08 pm
My problem is with the code.
Inside it we can find "#include<intro.inc>", but where's it!???
MPLAB indicates the file does not exist, so... what should I do???