Read Failed Auto Disconnect

[Chevvron]

Tom,
I have our original KFlop on the bench connected to a laptop with J3 installed to try and isolate the usb disconnect issue.
This is why I purchased a second KFlop and Kanalog.
This new combination initially would not connect on our 5 axis development machine until I unplugged another FTDI RS485 cable used for Modbus control of a VFD spindle.
We have had this same problem with more than one FTDI device connected with other devices / software without understanding why even though they have different names and serial numbers.
However with only the KFlop physically connected it remains connected using KMotion CNC.
I initially thought this might have been the issue with our original KFlop.
However our original KFlop Rev 1.1 does the following on power up :
Led D2 comes on briefly, D1 and D2 then flash,D1 and D2 remain on and KMotion CNC connects.
A few minutes or hours the Read Failed - Auto Disconnect message appears.
Sometimes D2 is on but not D1.
Sometimes D1 and D2 flash then remain on but no KMotionCNC connection is possible.
Sometimes D2 remains on but D1 is off.
Unplugging and plugging back in seems to work for minutes / hours until the Read Failed message appears again.
I have tried uninstalling the drivers and re-installing.
I have tried Flash Recovery and Re-Flash.
Any further suggestions ?
Regards,
Tim

[TomKerekes]

Hi Tim,

This new combination initially would not connect on our 5 axis development machine until I unplugged another FTDI RS485 cable used for Modbus control of a VFD spindle.
We have had this same problem with more than one FTDI device connected with other devices / software without understanding why even though they have different names and serial numbers.

I thought this issue was solved some time ago. Only FTDI devices with KFLOP, KMotion, or Dynomotion in the description should be accessed. What Version of KMotion are you running? Are you using the USB Driver from Version 4.35b? Device Manager Properties should show Version 2.12.10.0. With the FTDI RS485 plugged in how many devices does KMotion.exe show under USB Locations? If there are 2 does one of them work when selected?

However our original KFlop Rev 1.1 does the following on power up :
Led D2 comes on briefly, D1 and D2 then flash,D1 and D2 remain on and KMotion CNC connects.

That is what should happen for all Versions.

A few minutes or hours the Read Failed - Auto Disconnect message appears.

Does this only happen with the Rev 1.1 board?

Are other things connected to KFLOP? Kanalog? How is KFLOP getting power?

[Chevvron]

Tom,

The KFlop rev 1.1 now seems to remain connected as it has been on test on 2 laptops all week.
It was set up as USB power (J3 on) and KFlop only.
I don't know what was happening last week or before.

However the problem of the latest KFlop and another FTDI device remains on the 5 axis computer.
FTProg shows 2 devices but both have LOC id of 0.
USBview shows 2 devices with different LOC id.

Connecting the KFlop rev1.1 and another FTDI device on my laptop at home is okay.
FTProg shows 2 devices with different LOC id.
USBview shows 2 devices with different LOC id.

It does appear to be a problem with the 5 axis pc.

Both the 5 axis PCB and my laptop show 2.12.10 drivers for the KFlops and 2.12.28 for the second FTDI devices.

Any suggestions or ideas to try ?

Regards,
Tim

[TomKerekes]

Hi Tim,

I found this old Thread with some information although the issue doesn't seem to be resolved.

I understand there are some counterfeit FTDI chips with some issues and FTDI Drivers sometimes do strange things.

Do you have the capability to debug using Visual Studio to figure out what is going on? You could set a breakpoint where KMotionDLL.dll requests a list of devices to see what is being reported.

[geraldft]

This sounds like it might be related to a problem I have found when other FTDI devices, like a serial adapter is plugged into PC.

I will describe using the Kmotion utility program as an example...

If Kflop is plugged in and not the other FTDI device then all is fine. I can then plug in the other device and Kmotion continues to run properly.

Equally if both are plugged in then it will usually find the kflop and then it's ok.

However, if the Kflop is not plugged it will repeatedly interrogate the FTDI serial device, causing the program to run badly. This means if I want to run Kmotion "offline" I have to make sure the serial device is not plugged in, or else is in use by another program.

This might seem a minor nuisance, but it would be nice to find a way to identify that an FTDI device is not a Kflop, and therefore not attempt to lock it unsuccessfully... but still be able to connect if a Kflop does get plugged in later...

Any suggestions?

[TomKerekes]

I think that has been fixed? Have you tried with Version 4.35f?

[geraldft]

I haven't tried 4.35f.

Is it not something that can be done in the programming?

For example getting some info from the device before attempting to lock it? Then decide whether it might be a Kflop?

[TomKerekes]

Yes I believe the issue was that for some reason the FTDI driver in some cases takes a long time to return info on the non-KFLOP devices.

[geraldft]

Mmmm. Well I have some code for checking available serial com ports. I might try adding that to do a once only check and identify. If it finds a port I can prevent it from assuming it might be a kflop... and not try to lock it.