Help with an AVR version of the POV Display

[robertrndya]

VOILA!!!!!! it worked!!!!

Alright I now it works fine. I decreased the delay too much 1st, then gradually increased it until it worked fine.There may be still more FINE TUNING to be done but as of now its working.

Now I've tried your software which you provided with the "One Chip POV Project", but that software (POVConverterBigGraphics & POVConverterLong) just wont get installed. Can you tell me of some other software which I can use to convert images into HEX code (Taking into consideration the way the Excel Sheet works, i.e. each cell's hex value is converted into binary, the binary values are segregated column-wise and then we get get HEX code for each column and then we have the final HEX code). Is there a software which works like that?

I couldn't find a software that follows the Excel Sheet Pattern to generate the HEX code so I got a software that generates a binary code for 85x24 matrix and then I'm manually preparing the column-wise HEX code and believe me it's such a pain. My eyes hurt!! I can just see 1's and 0's in front of my eyes

Also i just realised that once I get the microcontroller functioning with the right code I wont need to program it again, I'll only have to change the hex code in the EEPROM (i.e. data to be displayed), so I can display any image at any time I want. Do you know of an in-circuit programmer that can program the ATmega16L AS WELL AS the W27C512 EEPROM??

Thanx and Regards,

Robert

[brad]

What error does it give you when you try and run the programs?

You may need to install extra software to get it to work and I think it would tell you what you require (if you don't have it installed already)

Unfortunately I highly doubt that there would be anything available - that is why I had to create the software myself. I guess the good news is that vb.net 2010 is free to download (it is included in visual studio) so you can make your own program to convert software. It obviously will take a little time to learn but you will find it an invaluable tool once you do. I have only been using visual basic for a few months and have created many graphic conversion programs with it, even ones that can make complete animations for LED displays!

You can also make an excel spreadsheet however it would need to be different to my excel spreadsheet because you're using an AVR which handles data in a different way to PIC's.

By the way, I used to do it the same way you're doing it and yes, it takes a long time!

Unfortunately I don't think you can get an in circuit programmer that can do both. I had to take my eeprom out each time to program it.

[robertrndya]

Hi Brad,

The error I get is regarding the missing microsoft runtime version. I think I'll start learning VB. Can you provide me the download link for that if you don't mind please (and any other documents that will help me learn that)? I'll also start searching the net for stuff.

And about the excel spreadsheet, the one you provided works fine after I expanded it for 24bits. I used the same spreadsheet to display my name. But I can't use it to display pictures because I ain't that good at artwork.

yesterday I tried some softwares which I downloaded from the net, but they don't give the right output (that I need). They give the binary and Hex codes for the pictures but not in the proper order like in the excel spreadsheet. I broke my head trying to generate the hex code manually, from the binary that the software generated, only to realize that the binary code was not in the proper order so I couldn't get the required hex code either.

I'll just try making a software that generates the hex code in the same format as the excel spreadsheet does. I hope I succeed in that though.

[brad]

What you need is the VB.NET framework:

http://www.microsoft.com/net/download.aspx

You don't need visual studio to run a visual basic program, you just need the framework installed. I guess it's similar to saying that to view a PDF file all you need is a pdf reader BUT if you wanted to edit a PDF file, you need to have a PDF editor.

Here's your link for visual studio (basic)
http://www.microsoft.com/express/Downlo ... sual-Basic

The best way to learn this stuff is to look at video's, I learned alot from this guy:

http://www.youtube.com/watch?v=_hsPfoOmNIM

This is a link to his first video on using vb.net 2010, he has a few dozen video's I think. Have a look at the video and then just do as he does, pausing as you go. You can find links on the right hand side of youtube to get all of his other video's

[robertrndya]

Hi Brad,

Thanx a lot for the links. I'm sure they"ll be of good use. Actually I had a querry about the excel spreadsheet that you provided. In that you provided the following colors - blue, green, cyan, red, purple, orange, and white. I wanted to add a few more colors to the spreadsheet like - pink, yellow, and brown. Now I wanted to know how do I incorporate these colors into the spreadsheet???
As you know PURPLE is derived from RED & BLUE and PINK is also derived from RED & BLUE. So what do I do to get a PINK, YELLOW, and BROWN color??

[robertrndya]

Brad, I just realized that in your 8x85 POV display you get the yellow (2nd 'R' and 'D') and pink colors (4th line before and after your name). HOW DID YOU GET THAT??????

[brad]

Hi Brad,

Thanx a lot for the links. I'm sure they"ll be of good use. Actually I had a querry about the excel spreadsheet that you provided. In that you provided the following colors - blue, green, cyan, red, purple, orange, and white. I wanted to add a few more colors to the spreadsheet like - pink, yellow, and brown. Now I wanted to know how do I incorporate these colors into the spreadsheet???
As you know PURPLE is derived from RED & BLUE and PINK is also derived from RED & BLUE. So what do I do to get a PINK, YELLOW, and BROWN color??

Unfortunately you can't get these other colours without incorporating digital to analog converters to your project. You can get a total of eight colours simply by turning on LED's segments in certain combinations. This gives you, RED, GREEN, BLUE, ORANGE, PURPLE, CYAN, WHITE AND BLACK

If you want other colours, you then need to mix different intensities of each red/green/blue colour for example all red and all blue gives you purple, however if you have all red and only a little bit of blue (I.E. red is more bright than blue) then you will get a much more reddish colour purple. If you want brown, you need to mix in alot of red, and a little bit of each blue and green.

Basically the more bits you have, the more colours you are capable of displaying. If you have a 2-bit DAC on each LED colour, then you end up with a total of 6-bits per LED which gives you 64 colours etc...

[robertrndya]

Okay, I just realized again that when I see the POV display the orange color appears like yellow and purple like pink, its only on the photos that they don't look like yellow and pink. VOILA!!!! OLLAYYY!!!!!

Now I got to learn VB, and FAST!!!

[robertrndya]

Hi guys,

I have 1 more query now. Do you know any isp programmer for the w27c512 EEPROM?? I'm using an smd plcc w27c512. Please give me some suggestions.

If my statement does not make any sort of sense then please forgive me, my brain is zapped.

By the way, I'm learning VB from the links you gave me. And I'm trying to write a code for the rgb conversion.

Thanx.

[brad]

Hi guys,

I have 1 more query now. Do you know any isp programmer for the w27c512 EEPROM?? I'm using an smd plcc w27c512. Please give me some suggestions.

If my statement does not make any sort of sense then please forgive me, my brain is zapped.

By the way, I'm learning VB from the links you gave me. And I'm trying to write a code for the rgb conversion.

Thanx.

Unfortunately I don't think that you can program EEPROMS while they are in circuit. One such problem I can see is that to program an EEPROM you need quite a high voltage (I think around 12Volts) to be applied to the EEPROM.

Make sure you let us know how your vb programming is going. Even ask questions in the VB forum.

[robertrndya]

Hi Brad,

I have posted my query on the vb forum under the topic Graphic Converter for LED POV Displays. Please check it.

[robertrndya]

Hey Brad,

I've modified the c code for displaying 2 frames (2 pictures), but the POV display just wont display even 1 picture. It just displays some random colors across the LEDs which remains constant. The LEDs don't even blink. When I run the simulation in the compiler it works fine but when I test on the POV it doesn't display even 1 image. What could be the reason for this???

I've programmed the EEPROM with the right data. And in my source code I just copied the FOR Loop that's used for displaying the image and pasted it after the 1st FOR Loop. I put the necessary address to get the 2nd image from. My brain isn't working now and I feel too drained to try anything now. Please suggest something.

[brad]

It's quite hard for me to suggest something without seeing the code, you could paste the code here but then I can't be certain that I could follow it and find the problem because I don't program in C.

There could be any one of a huge number of reasons it's not working, maybe one suggestion is that your microcontroller is constantly under reset? but not in the simulation, it's just too hard to say at this point.

[robertrndya]

what was the problem you faced with the 32x64 POV???? For me, I'm getting a different colors everytime I connect the power supply. And this combination remains constant until the power supply is removed. It's pretty much frustrating when you can't understand where the fault is.

[bitfogav]

Post your code! and double check your circuit..