K8055 Will not initialize

G’day Folks, from a ‘newbe’ to Velleman in Australia

I have just purchased and assembled a P8055 USB interface kit and after installing the Velleman test program supplied on their disk, plugged it into my PC.

The ‘power’ Led on the board lights, indicating that it has power from the USB port
The #8 output Led flashes twice then stays on all the time.
(Not just blinks once as the instructions say it should.)
To me this looks like some form of error code, which doesn’t help me as I have no error code cheat-sheet.

The testing program in the PC says that it cannot find board #0.
Both sk5 and sk6 have links.
I have tried all 4 possible addresses just in case.

The operating system (Windows XP) tells me that the PC does not recognise the USB device.
When checking the system it also says that it could not find the DLL files…I thought that these would have been loaded when I loaded the test program ?
Was I mistaken ?

Is this a problem that has surfaced before or does somebody out there have any ideas or do I have to take the unit back to ‘Jaycar’, the retailer that I purchased the unit from ?

I have re-checked my soldering and can see no obvious shorts or dry joints.
Before I retired I spent much of my working time designing and building self contained microprocessor systems.

Unfortunately I have had no experience with playing with USB ports, much preferring to use RS232 ports… unfortunately no-body else these days seem to think the same.

Thanks in anticipation


Hi Adrian,

there have been similar reports like that from Windows 7 users. I think the conclusion is that this is caused by timing issues. Some of those threads have solutions.

google.com/search?q=k8055+wi … =firefox-a

Do you have any other computers available, that you could connect the card to? That way you could at least see if you get past that steady LD8.

The K8055 is an HID USB device. As such it does not need special drivers. That also means that you don’t need to “install” anything on that other computer. You can just put one of the demo programs (plus the K8055D.DLL) onto a USB stick and try to run it there.