K8055 Kit version not working

Kits PC Related Projects
1

Hi,
I have built a kit version of the K8055 USB experiment interface board. I have installed the software on my laptop.

I then followed the instructions toset the address on the board and then plugged in the board to the USB port. The power LD11 comes on but the LD4 does not flash. When I click ‘Connect’ the software says 'port n not detected. I have checked soldering and it appears ok also tried all card addresses.

Any suggestions as to possible faults and is there a fault finding guide available?

Many Thanks

2

The lack of LED LD8 flashes indicates that the microcontroller IC3 is not starting to run.
If you have a digital voltmeter (DVM), please check the pins of the IC3 that there is +5V on pin 1 and +5V on pin 20. Check also that pins 8 and 19 are connected to GND. If this is the case then you may try to measure if the crystal oscillator is running. You may measure the DC voltage on the pins 9 and 10. The voltage on these pins must be between 1.5V and 3V.