Image writing / verification failure in SpokePOV 1.0a

[maxgahr]

Hello,
I have the SpokePov 1.0a kit (according to PCB text, I believe the bag label said 1.1) and a Parallel dongle, XP on a desktop computer. All lights flash up in order when I connect batteries (then one LED at the end stays on at one side of the SpokePov, on the other side it is the 6th from the button -- see image). I have installed giveio and the dongle passed the communications test, using a MultiMeter.. I can connect to the SpokePOV, read from it (will make the wheel entirely red on my screen, write to it any image (it will not complain), but when I verify it, it fails (either immediately after i press the button or after a few blocks of verification). Then, when I read the bank again after writing any image, it will return the full-red wheel image again. This tells me the write process (during which the LEDs light up in order) must not have worked. I have tried Software 1.4 and 1.2, same effect, although 1.2 seems to communicate slower. I tried one image to a bank, then try to verify it (one at a time) and writing all banks and then verifying, same effects. I do not change any values like mirroring, rotation offset, animation timing, comm delay etc. The batteries should be spanking brand new. The fact that it behaves just nicely except the writing/verification makes me think that something with the storage chips is not OK. But then again, I dont have much expertise.

If I wanna hang out with the other SpokePOV kids at Burning Man, I need to fix this before Saturday...

What's wrong? Any ideas? Thanks for the help!



http://www.ai.sri.com/~hessling/ladyada/pcbFront.jpg

http://www.ai.sri.com/~hessling/ladyada/pcbBack.jpg

http://www.ai.sri.com/~hessling/ladyada/front1.jpg

http://www.ai.sri.com/~hessling/ladyada/front2.jpg

http://www.ai.sri.com/~hessling/ladyada/front3.jpg

http://www.ai.sri.com/~hessling/ladyada/front4.jpg

http://www.ai.sri.com/~hessling/ladyada/back1.jpg

http://www.ai.sri.com/~hessling/ladyada/back2.jpg

http://www.ai.sri.com/~hessling/ladyada/back3.jpg

http://www.ai.sri.com/~hessling/ladyada/back4.jpg[/url]

[adafruit]

Hello,
I have the SpokePov 1.0a kit (according to PCB text, I believe the bag label said 1.1) and a Parallel dongle, XP on a desktop computer. All lights flash up in order when I connect batteries (then one LED at the end stays on at one side of the SpokePov, on the other side it is the 6th from the button -- see image). I have installed giveio and the dongle passed the communications test, using a MultiMeter.. I can connect to the SpokePOV, read from it (will make the wheel entirely red on my screen,

it sounds like your spokepov is working just fine but that the EEPROM itself is bad. or it could be the wiring to/from the eeprom.
if you have more than one spokepov I would try each of them. the 4k eeproms are preprogrammed these days. so if you have another one try reading from it BEFORE you write to it and see if something shows up. should be like a biohazard.
make sure the EEPROM is in the right way
make sure none of the EEPROM pins are bent so that they are not in the socket

only use the latest software. thats v1.4

try changing the rotation offset. does that 'stay'? or can you not actually change it.

i have removed the enormous images. in the future, only post links to the images. thanks!

[maxgahr]

Thanks. I have followed your instructions and still no success. The Soldering seems OK and the EEPROM is in the correct direction. Unfortunately I dont have another SpokePOV to try the other experiments you suggest.

I can change the rotation offset, and when I re-connect, it will display the new value.

Some interesting observations on the software:
After setting the rotation offset, I can connect to the spokePOV, but no image of the wheel is displayed. Everything Gray below the buttons "Disconnect", Rotation offset etc.

Also, even in my previous trials, it struck me that the software would display 32 frames at some point, at others only 4 frames where I could paint images. It varied from connect to connect.

What can I do? Can I buy another EEPROM at Radioshack or so?

Thanks!

[adafruit]

the software is freaking out because its trying to calculate how many banks you've got by reading the EEPROM data but its getting back nothing.

You can return to me the EEPROM and I'll replace it. Mostly interested in how it failed (if in fact its the EEPROM)

[Szuts]

Hello,

I seem to be experiencing the same problem as maxgahr. I'm using SpokePOV v1.1, a USB dongle, and software 1.4 on OS X (tiger).

I can connect to the spokePOV fine, but always see 32 banks of images. Reading from any bank returns an all-red image (all pixels on), and although I can write to any bank without error, reading back the same bank, even immediately afterward, returns an all-red image. Verify only passes if the image displayed on-screen is all-red.

Likewise, when I change the rotation offset, disconnect, and reconnect, no wheel image is displayed. Changing rotation offset back to default (255) and reconnecting gives the same 32-bank problem just mentioned.

To troubleshoot this, I've verified that all LEDs are functioning normally and the soldering and chip orientation are fine. I replaced both the EEPROM and the PIC with chips from another spokePOV kit and had the same problem.

Can you suggest anything else to try? Did you confirm that maxgehr's was an EEPROM error? It's very strange to see this problem with two different chips, unless I'm accidentally frying them.

[adafruit]

if you tried 2 different ICs and they're both freaky
its probably a soldering thing
look at the PCB, check for bad solder points, etc!

[jaingaurav]

hi everyone,

The same thing happens when you remove the EEPROM and try to write the image.

I have tried it.

[OSTIN]

Hi!
I have a small problem. I use memory AT25320, software version 1.4, serial interface. The program connects to spokepov and sees all 32 memory banks, write there pictures, but when reading the screenof the program all red : (. I am using two batteries 1.2V. In what may be the problem?

Sorry for my english, thank you!

I use AT25320AN-10SU-2.7, may not have enough voltage?

[adafruit]

do you have a spokepov KIT you purchased or are you designing your own?

[OSTIN]

Hi!
I trace PCB for SMD components on your circuit. Today, I want to change the resistors 39 ohm to 100 and use three batteries to power. Maybe this will help.

it is:


Thank you for this project!

[OSTIN]

I removed all the resistors are 39 ohms, connect the power supply 3.6 volts. As a result, the program has ceased to see spokepov memory banks: (
I bought a chip 25LS040A try to put it.

[OSTIN]

I'm sorry. I made a mistake in PCB. Now EEPROM reading and writing successfully, continue to build.