Is failure with the k8055 kits common? I have a reasonable amount of electrical engineering experience, so… yea. I bought one k8055 kit and assembled it. 2 blinks of LED08, then it stays on solid. Exchanged kit at RadioShack (took some arguing) and… same problem. I’ve checked every trace, as well as all the components other than the 4 ICs.
Device Manager shows “Unknown Device” and warns it is receiving corrupt responses to probe attempts.
Getting it exchanged the first time was bad enough, but now that they’re on clearance I CAN’T get it exchanged. Now what am I supposed to do? I feel like I’ve lost an entire weekend of work, not to mention the $85 + 20 miles of driving. le sigh
Anyone got suggestions for fixing this?
–Matthew
I would not call it “common”, but what you describe isn’t unheard of on this forum.
LED 8 blinking 2 times then turning on solid means that the PIC is running (that’s good), but the USB module in the PIC’s firmware wasn’t able to enumerate properly (that’s bad).
It is unfortunately not easy to exactly pinpoint the reason for this. If you search this forum you will find threads suggesting the use of a powered USB hub for the connection. We also know that the original K8055 (not the K8055N) has a bug in the USB descriptor, which causes DirectX crashes on Windows XP.
Another thing to look at would be rosin flux residue, if you used flux or rosin core solder. It introduces noise into high frequency circuits. USB has very strict timing constraints. I have had PIC prototypes working fine except for USB communication, when the oscillator isn’t “clean”. If that is the case, try washing off the residue with a tooth brush and denatured/rubbing alcohol.
If would be best to post some pictures of the top and bottom of the board (on a free picture based web server)
You will need to make sure they are VERY CLEAR and SHARP.
Maybe some one can find the cause of the failure.
You might try it on a different computer to see if there maybe a problem there or try a different cable.