API function may return 64 when it occurs the USB communication error with USB device.
Please use the USB cable which is attached with CONTEC's device if you
use the USB cable (or USB extension cable) made by the other manufacturer.
And also, CONTEC recommends to connect from PC to CONTEC's device directly
with the USB cable which is attached it if you use USB Hub from other
manufacturer.
Here are the other suspected causes.
1. Too many the electrical noise around USB cable.
Please try to add the ferrite core on the USB cable.
It is included the ferrite core on some of
CONTEC's device.
Please refer "Product Configuration List" on the hardware manual
to confirm it.
2. Uncertain connection on USB connector. (Or unplugged and plugged USB cable during operation)
Please make sure the connection fasten for
USB cable.
It may be other approach to replace to the new USB cable.
3. Not enough electrical power for your USB device.
Please confirm the power consumption and the power supply type of your USB device.
On the case of Bus power, please make sure
the total power consumption from your PC.
It may be better to unplug the other external USB devices and to connect
the only CONTEC's USB device.
On the case of Self power, please make sure
your power supply can generate the enough electrical power for your USB
device.
You can also buy the electrical power from CONTEC. And you may find the
model number on the hardware manual.
4. It may be already broken your device.
Please contact the technical support center (TSC) of CONTEC and report your situation to CONTEC.