Well: John highlighted the **ONLY** safe solution.
We tried the Timy's USB connection extensively, with many PCs, different versions of Windows, different hardware connected (i.e. score boards,
modems, mountain wires, etc.), and after all, we were simply left without hope.
Basically, any glitch, any ripple generating EMI/RFI happening anywhere around the Timy, will hang all communications.
Whether the problem resides in the USB driver or in the Timy hardware, or more probably both is still unknown, but if you want to work smoothly, without being afraid of everything happening around you, you must definitely avoid the USB connection with the Timy.
Yes, the classical anti-EMI/RFI strategies may help somehow, but with some side effects. We tried using optocoupling on inputs and outputs, HI-Q shielded USB cables (max 2 ft) and insulating transformers for power. It was
partially working, but with an inacceptable number of extra devices around the Timy. Partially means that even the proximity of the big CC motors of the cable cars gave high noise on the wires, and every day we discovered something new that could easily block the communications.
I has been frustrating. The final decision was to rely on serial.
Cheap, rock-solid, highly reliable..... could you ask for something more than that?