I have built a K8055 using the original Velleman kit.
On plugging in the board to the USB port of a PC, the power LED LD11 comes on and stays on,
but the LD8 LED does not flicker nor does any other LED light.
Using the USBView,exe program shows that it is not recognised by the PC.
I have tried several ports on my HP Desktop PC, running Windows/7 64bit and a Samsung Netbook NC10, running Windows/XP.
Also, as expected, the Demo programs show the card is not detected. I have downloaded the latest K8055_DLL_4.0.0.2_connected.zip.
On reading through the forum I found that Thomas.Heppner had got the 220nF and 100nF capacitors swapped.
On closer inspection I found that I had done the same - I had C7 and C6 swapped (i.e. the 220nF was in C7 and 104nF in C6).
I de-soldered them and put them in the correct locations, but sadly the problem remains the same.
I checked the Quartz crystal on an oscilloscope and it is running at approximately 4Mhz but I don’t know how well the scope is calibrated.
The voltages on the pins on IC3 are all at, very near 0v except for these:
P1=0.217v, P6=0.440v, P7=0.436v, P9=0.839v, P10=2.46v, P20=5.18v, P18=0.56v, P17=0.56v
It has been many years since I worked on electronic projects and my eyesight is not as it was,
however, I don’t think I have any dry joints or solder splashes.
I have included some photos of the board back and front, taken before I swapped the C6 and C7.
These can be downloaded at: dropbox.com/sh/41w9piwzlkkn4m1/Qj-3norU5d
The names of the images have -A indicating they were taken in Artificial light whereas those with -D were taken in Daylight.
There is also a photo of the reel of solder used.
I don’t know if I damaged anything by having the capacitors swapped, but I don’t know where to go next.
Please can you help or advise?
Regards, Chris