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Topic: VGA library - now with TV output (Read 34735 times) previous topic - next topic

est_cap

#75
Oct 01, 2014, 05:11 am Last Edit: Oct 01, 2014, 05:13 am by est_cap Reason: 1

Hi for high resolution it' simple you simply use R G B directly to the SPI MOSI

For color low res, I dont have the module with me since i'm not home, but check out the resistor value on the board and place the RED BITS in so it match le library reqirement same for GREEN. For the blue part, i was satisfy by using the 2 lowest pin BLUE 1 AND 2, but you might want to try all the combination. But one thing is for sure, the library only handle 2 BLUE and not 3.

Thank you! If it wasn't for your straight forward answer I would be still looking for advice to be sure I wouldn't fry my Due  :smiley-mr-green:
I tried as you said, discarding the B0 and worked straight forward. I will try switching between the B pins just to see the changes.
Now I am going to try the monochrome hi-res output. This module is great!

You mentioned something about the PS/2 keyboard messing up the video output... did you find a way to circunvent this? does that happen both in colour and monochrome?
Thanks again!

Just in case anybody else has this module, this is the wiring I used for the colur mode:

Quote

ModulePin DuePin
VGA_R2   41
VGA_R1   40
VGA_R0   39

VGA_G2   38
VGA_G1   37
VGA_G0   36

VGA_B2   35
VGA_B1   34
VGA_B0   Not connected

VGAHS   43
VGAVS   42
GND GND

Frédéric_Plante

Not yet, but I'm working on it, that is why i'm passing the word along to try to put as many people as possible on the case.

It's working, but the image skip while receiving the data. i use 3.3v to power on the keyboard by the way, to protect the Due
As we fight our way northward into the great unknown, only that one thing remains certain...

Frédéric_Plante

In lower resolution, the problem is not as bad, but still there. Like I said, my hypothese is that it use an interrupt on the DUE to catch the clock signal of the keyboard.
As we fight our way northward into the great unknown, only that one thing remains certain...

est_cap

I remember having this kind of issue with my other arduinos (Mega 2560 and NanoR3) using TVOut.
Using the PS2 library would cause the TVOut crash completly (not just flicker as you say it happens in this library)

In this thread http://forum.arduino.cc/index.php/topic,75608.0.html the author states the issue without solution.
Could it be possible for the Due to use other techinque rather than interupt based? I don't know most of the extra features the Due has, but I guess there might be other way.

Frédéric_Plante

I was thinking that including the scheduler in these operation could fix the thing. i just did not have time to try it yet. The multi tasking aspect has to be the solution.
As we fight our way northward into the great unknown, only that one thing remains certain...

est_cap


I was thinking that including the scheduler in these operation could fix the thing. i just did not have time to try it yet. The multi tasking aspect has to be the solution.

Do you think using a 2nd Arduino (Nano) to read the PS/2 signals and sending via Serial would evade the problem?
Connecting the GNDs pins of both Arduino would damage them if they are connected to same power source? (in the VGA module, I think the PS/2 and VGA GNDs pins are joint)

Frédéric_Plante

#81
Oct 02, 2014, 12:56 am Last Edit: Oct 02, 2014, 01:01 am by Frédéric_Plante Reason: 1
Yeah that was my second bet. I mean to use a 3$ MINI 3.3volt 8mhz as a keyboard controler. This kind of Arduino also use 3.3volt so no need to use a level shifter. 

The gps example in the library show that the usage of the serial port does not bother the display.
As we fight our way northward into the great unknown, only that one thing remains certain...

Frédéric_Plante

Yeap I confirm, if you use a Nano you will need a level converter, and if you use a Mini 3.3volt, you can hook straigt the two Arduino
As we fight our way northward into the great unknown, only that one thing remains certain...

est_cap


Yeap I confirm, if you use a Nano you will need a level converter, and if you use a Mini 3.3volt, you can hook straigt the two Arduino

I ended up using the USB Keyboard and leaving the PS/2 port without use.
I *finished* implementing the basic  I/O of Keyboard-VGA for the Bitlash 2.0 project (or pseudo OS) for the DUE, and I am implementing the SDCard now  :smiley-mr-green:

I'm using the the Due VGA library in monochrome 800 x 600, for a project. The library uses the MOSI pin for video out to the VGA. After a while I needed to add an SD card. How do I use SPI now, with the MOSI pin already occupied with video signal generation?

Is it possible to move the video output to another pin, or is there a way to use an alternative SPI? I found an SD card library from Adafruit that allows one to specify any pins for MOSI, MISO, SCK and CS. But that library did not work...

Can someone please help me with this problem?

Hello community!

First thanks stimmer for this library, its wonderful, I Have a mistake, could you or other user help me please.

I made the TV out circuit and works fine, with no good color i think due I did not use resistance precision values, but in general good.

And i made the VGA color circuit but i had a issue, i did not get any picture in my monitor when i connected it.

I had a mistake in the circuit diagram because in your blog (http://stimmer.github.io/DueVGA/breadboard.html) you don't use MOSI pin in VGA color only for monochrome, and later i saw in this forum your circuit using 3 SPI connectors with a 220 ohms resistances, and i don´t know which one to use or what other change do i have to do.

Thanks for help!

paiarunk

Hi

I need to make 640 x480 resolution ?

Any help??


Arun

mcnobby

I need to make 640 x480 resolution ?
You would need at least 38400 bytes just to store the screen bitmap for a monochrome display at 640*480

If you wanted to try and to text on the fly at that resolution you probably wont manage it at 16MHz
while (z--) { snoreEvenLouder(); }
www.smartshow.lighting - www.dmx512.lighting

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