initialization

[cncdrive]

The idea of a bad soldering joint does not makes much sense, because if the issue was that then why would the issue connected to a PC turnoff and turn back on event?
I mean if it was a bad soldering joint then the issue would happen anytime not only when the PC is shutdown and turned back on.
An USB connects via 4 wires, the Vcc, GND, D+ and D- wires. The recognition like all other datas go through these 4 wires and there is no specific pin on the USB IC which is only for recognition of the chip.
The recognition on a PC works like the PC sends out some packets asking the device about who he is and then the device answering back etc. so, the recognition is basicly a few data packets exchange between the PC and the USB device and this data exchange happens on the exact same channel as all other communication. So, if there was a soldering issue then not only the recognition would not work properly, but also other communictions, normal communication/working would not work properly.

I think that the issue will be something with the computer, like USB chipset or chipset drivers problem or somekind of Windows problem, but honestly I don't know what it could exactly be.

[Sailor]

I only offered the bad solder connection as a possible cause, they can be intermittent based on how much strain the cable may be putting on the connector. My real concern is more with the communication of the device with the computer, and because I have had multiple USB items connected to the computer during my ownership, I find it hard to believe that it is the computer. Unfortunately, it is near impossible to diagnose this kind of intermittent problem. I already have over a week of lost production. The first one I had just stopped working, no green light. Had to wait almost a week for a replacement. This one initialized just fine and updated the firmware, after that the reliability became a problem, so I am thinking it is more of a problem with the firmware and/or its drivers. I have updated all of my USB drivers for my computer as well to try to alleviate that problem.
You stated

The recognition on a PC works like the PC sends out some packets asking the device about who he is and then the device answering back etc.

I believe that it is this initial communication which is breaking down. And yes, it could be from either end. The programmers and designers of this product should be reviewing my concerns and offering suggestions or possibly asking me to help them resolve this problem.

I can't lose another week of production so if that is the route I have to go, I will seek out a different vendor. In the meantime, I will try to identify the cause.

I just connected it to the front USB port and it showed up immediately on the USB list in device manager (after restarting the computer) I will keep an eye on this and report back any change.
Regards,
Sailor

[cncdrive]

I believe that it is this initial communication which is breaking down. And yes, it could be from either end. The programmers and designers of this product should be reviewing my concerns and offering suggestions or possibly asking me to help them resolve this problem.

The initial communication sequence is not something the programmers or designers do/did, that is handled automatically between Windows and the USB chip,
that sequence is built into the USB chip and Windows, we the developers did not make it and can't do anything about it. It just works as the USB chip is queried by Windows about it's properties.
If it does not work properly then something is wrong with the connection or with the computer or with the USB chip itself.

I just connected it to the front USB port and it showed up immediately on the USB list in device manager (after restarting the computer) I will keep an eye on this and report back any change.

As I said and suggested previously the issue might be a dirty/broken USB port or a USB chipset problem of the computer which both could be possibly resolved using a different USB port/hub.

[Sailor]

I did not know that the USB chip was preprogrammed for the communications, I only assumed that it was not but controlled by the firmware of the device. Good to know this. I had tried several different ports on the back of my PC, the one next to my WiFi connection I thought should be reliable as WiFi always works, no matter where I had plugged it in.
I will, as I said earlier, keep the forum informed as any of this may be useful to someone. Recycled machine several times since the last post and it is still functioning. Yay

[CT63]

4 port, 3.0 USB cards with up to date chip sets are available for around $15-$20 on Ebay and other vendors. Might be worth it to simply get a new USB card.

The other thing worth checking is make sure the USB driver "allow sleep mode when not used" isn't selected in the "power option" for the driver.

[cncdrive]

Yes, the USB chip makes all low level stuff itself including the initalization routine, the microcontroller/firmware has nothing to do with that.
If you would tie the USB chip on a USB cable without anything else connected to it, just a few capacitors which are required for operation then it initialized itself on the USB port and would appear in the device manager. The only thing we do with the USB chip is we programmer our own vendor and product IDs and product description string into it's EEPROM, so the chip can tell Windows that it is our device and is called a UC motion controller.
And based on that the UC100 is a relatively old product, it is out for several years (it is our oldest motion controller) we have a relatively large amount of users, tens of thousands of UC100 controllers are out at customers, this is why I'm 100% sure that there is no problem with how the device initialises itself on the USB port, because if there was an issue like that we would definately hear about it already, but we did not.

[cncdrive]

The other thing worth checking is make sure the USB driver "allow sleep mode when not used" isn't selected in the "power option" for the driver.

Yes, it's important to disable to USB suspend function in the Windows power management, otherwise Windows can stop communicating and can virtually disconnect the device whenever Windows thinks you don't need it.
However the sympton that the device just not showing up on Windows startup says that it should be something else and not the USB suspend function of Windows.

[Sailor]

I am learning a lot about USB, Thank You!

USB driver "allow sleep mode when not used" isn't selected

Where would I find that? I have turned off all sleep or hibernate in the Power Scheme of Windows, with the exception of allowing the display to darken after 30 minutes.
It seems using the front panel USB port is working, will know for sure in a few days. I may try a powered USB port, which I have to see if that resolves the problem on the backports, more curious now that I know more.
In all my years working with computers (42 years), I never experienced a problem such as this, but see that others have so I was able to get some really good information from their experience.

Thank you all

[CT63]

Control Panel --> Device Manager --> Universal Serial Bus Controllers --> Locate the UC100 USB and open it.

Click "Power Management" tab and uncheck "Allow the computer to turn off this device to save power". This option is for laptops to save battery power and Windows defaults to the "on" mode.

If the USB port on the PC is failing an external powered USB hub will be of little benefit.

[Sailor]

I Moved connection to the USB port on front panel, seems to have resolved the problem, will know in a few days. Not the cable thus far, not the length of cable, although I have not gone back to the extended cable, but the USB circuits on Windows 7 maybe?

Really frustrating, at first it looked like a cable problem, but even though it connected once, later on recycling the PC, the connection would not initialize, then I moved to short cables and connected once, later on recycling the PC the connection would not initialize, then I changed to different ports on the back of the PC, connected once, later on recycling the PC, the connection would not initialize, now on the front port next to my mouse and keyboard dongle, and it appears to be working there. I have recycled PC multiple times and the connection reinitialized after power up each time. To me, it still appears to be a problem with the unit as it should not be so sensitive to be so selective when other devices have no problems on the same ports, such as my WiFi. It is also possible that there may be a ground loop problem and I have ordered a new break out board to resolve that, perhaps the front port due to its wiring is not as sensitive to that. Who knows? (Rhetorical Question).

Again thank you for all the insight everyone has provided Once I get the new BOB in and connected I will update this area. I expect to test it on the other ports because I am ANAL that way, I want to know if possible if it is resolvable.

A question along this path but not directly related: From the output of the UC100 to the input of the Stepper Motor controller, what would be the maximum length of DB25 connected cable that would be acceptable? I am still trying to move the PC away from the CNC Router because of the fine dust created.