Hi Brad ,

Thanks for this web site.

I made 8*85 POV with my own PCB and to test it I programmed eeprom 27c512 very simple one frame as you can see in the attachment excel (first frame) But after I turned it on I noticed that there was a confusion on the frame image .The leds were lit like as in attachment second frame. I checked pcb many times , read instruction that you wrote and changed motor speed but nothing has been changed.If you can understand something from these frames you could you please tell me what I did wrong and how can I fix it.

http://www.bradsprojects.com/phpBB2/download.php?id=79

At first glance it looks as though your data is there, although it is getting mixed up.

Is your address bus connected properly? are you incrementing the address bus correctly?

can you give any more information?

thanks for quick reply...
When I saw the image first time , I thought I mixed something on the board then I checked every wire , bus ,companent ,etc.
So address bus and increment are correct.I dont think there is a hardware problem .I checked many times with schematic , Dai Omie PCB
and everythings are same.But I am suspicious about the 27c512 programming. There is something strange, could you please check the attachment file .I added printscreen of programming 27c512 step by step.
I think , I might have a mistake while programming .( I have very little experience about Pic, Eeprom etc. .I just did this project by follow the explanation )

http://www.bradsprojects.com/phpBB2/download.php?id=95

Could you also upload the hex file and a screenshot up what the opened up hex file looks like in you programmer software

I upload the files that you want

http://www.bradsprojects.com/phpBB2/download.php?id=99

Thanks for the uploads.

Everything looks okay as far as the .hex file goes. It should be drawing the arrow just as you wanted.

Unfortunately I would have to see the project for myself in order to help anymore with it.

I will be uploading my new and much simpler version of this project that only uses one chip. If you wanted to build that I think you would have alot less trouble.

Ok this is just an idea? Have you added the the pickup sensor and placed a nail or some kind of object to mark the start point of the display?.

I noticed that (ibrahim) has mentioned that he has changed the speed of the motor but this doesnt seem to make any difference?

Im thinking that if the microchip has not seen the pickup sensor? then it wouldnt know when to start to display of the picture or in this case the arrow?

Also dont the eeprom 27c512 need tobe ereased under a U/V light before
reprogramming it again?.

This is just some ideas, I might be totally wrong but just thought I would try and help

You make some good points there.

Although, the POV would not display anything if there wasn't a sensor OR if you removed the one line of code where it checks for the sensor.

Also, bitfogav you gave me an idea. Have you read your eprom after programming it to see that the data contained in it is what should be there?

Thats a good point too Brad, check the eprom has the correct data on it after you have programmed it..

Also are you sure that you set the frame correctly in the souce code ibrahim?

Exaple:

Hi all,

I did everythıng that you told but unfortunately nothing has been chanced.It seems , I missed something which I could not find, so after nervous breakdown ,I made it scrap and I decided to built again POV project from beginning with new PCB .
I will let you inform when I finish new ones
Thanks for your all support .
God bless all of you.

That's unfortunate. But remember it is all a learning experience!

hi Brad,

1st of all thanx for activating my account. I just thought I might post here now that my account is activated. Have you read my last 2 posts on the "instructables" site by any chance?? Anyway i'll just brief you on my latest problem.

I enable the RESET pin of the ATmega16L after every display of my frame so I have got rid of the garbage values. Now I get the required colors on the LEDs for the output which reads "ROBERT". But when I tested it on the ceiling fan I could only see the colors but not the letters. The letters were just not appearing. Could it be something to do with the delay when the LEDs are ON "as well as" OFF??

Another problem is that I had prepared the circuit on the breadboard and I mounted the breadboard on the fan in spite of knowing that the wires would come out (and a few did come out, but I was just too eager to test it). Now I wanted to prepare the PCB version of the circuit for further testing but am discouraged by a friend about preparing the PCB yet. He says that I'm not getting the letters maybe because of some mistake in the circuit (although I think otherwise since I feel that if he was right then i wouldn't be getting the right colors on the LEDs). The LEDs flash with the right colors but the letters just don't appear.

What do you suggest? Is it OK if I prepare the PCB? Where do you think does the problem lie?

Thanx in advance.