Failed to open COM port on windows 7

[alexbb]

Hi,

I'm using the latest stable release of the LogicSniffer client 3.08, and it's unable to connect to the open bench logic sniffer, displaying

"Capture aborted! Failed to open/use COM2! Possible reason: No such port!"

I've tried changing the COM port in the device manager, Enabling/disabling the device to no avail. Any help would be appreciated.

[ian]

Hi Alex,

What is the operating system? Do you have your own copy of Java 7 installed? Those are two issues that cropped up lately.

Have you updated the Logic Sniffer hardware with the latest 3.08 firmware/bitstream?

[jawi]

Does it work on any other platform, like Windows Vista/XP or Linux (presumed you've got such a platform at your disposal)?

Otherwise: did you upgrade to the latest firmware, and can you run the firmware-selftest routines with success (see http://dangerousprototypes.com/docs/Log ... er_utility)?

[edit]drats, Ian, you were quicker than me :)[/edit]

[alexbb]

Hey guys,

I've tried it in a Ubuntu 11.10 through VirtualBox, the same problem. In both Windows 7 and Ubuntu it will work at first, I'm able to capture and it displays correctly, but after a few times of hitting "Begin capture", I get the "Failed to open..." error. The Logic sniffer has the latest Demon core bitstream on it, and the PIC's firmware has been updated. I'm at work right now, once I'm home I'll try the firmware-selftest routines.

Also, note worthy, I'm using the ols full versions, with the JRE included in the archive.

[Bruggen]

Hi Folks,

I just got my sniffer yesterday and started capturing data. After about an hour or so I started getting the same error. Device manager recognizes the sniffer and can enable and disable it, but the L A Client doesen't see it.

[ian]

Hi Bruggen - I'm sorry about the problem with the OLS. You're on Windows 7, and it did work for a while but later stopped?

[sherman111]

Any progress on this issue? I have the same problem running win7 64 bit. COM port driver fails randomly, BUT fails consistently when I plug in another device. The only fix I have found is to reboot and restart everything, being sure that OLS is the last thing I plug in. The OLS is running off a powered hub and getting a solid 5V, but I wonder if there could be a transient when I plug in another device. I'll try a massive cap across the power pins and see what happens.
Another, I think related issue, is the driver sometimes shows up on COM9, sometimes COM10, sometimes both but only one works, and sometimes hops from one to the other. Very strange. Any ideas appreciated,
Sherman

[AndThen]

The changes between ports are what happens when a device resets faster than windows can remove the prior device. If it's randomly hopping ports It is likely being reset(brown out maybe). For manual resets it is helpful to have the device manager open so you see when to release the switch.

I know it is windows but you really shouldn't need a computer restart. If you close the client and disconnect the OLS does the device/port remove it's self?

[arupbsk]

Run the program with administrative rights by right clicking and selecting "Run as Administrator". It should be able to access the port then.

[sherman111]

Thanks for the suggestions.

AndThen - yes. brownout was my theory but I run it off a powered hub with a stiff 4A power supply. i tacked a 330uf cap across the USB power pins on OLS and the problem persists. I'm not sure I follow the "resets faster than windows can remove the prior device." Why should there be a device to remove? Does OLS reset, then reasserts itself, trying to claim a resource windoze hasn't freed yet? Sounds like an OLS bug if it is resetting rapidly when first plugged in. The 2 ports appear when I first connect the device. It loses the port sometime after it's connected and I cannot restore it. Removing/reconnecting OLS does not work. windows reports the port as operational after the failure. I suppose there are things i could do as admin...

Arupbsk - yes, I should run it as admin so I can poke around more effectively. Strange that I so often forget that I can do that.

If I'm careful I am able to get an hour or two of debugging before losing the port, so it's a relatively minor annoyance, except when i have gone to a lot of effort to set up a test and it decides then is the time to choke. Regardless, it is the best $50 LA I have used and gets the job done. If I could afford Tektronix I would have it :-)

Please keep the ideas flowing. Is there any FPGA guy out there able to put edge triggering on a few inputs? That would be so nice.

Thanks,
Sherman

[Qwlciguk]

I don't have any comment about the port issues that you're encountering, but edge triggering is already possible via trigger sequence. Just define the first state as low and the second as high and you'll have a positive edge trigger. It's a bit of a pain by comparison to commercial logic analyzers that offer a direct edge trigger selection, but it's better than nothing. I suppose the client could offer an automatic sequence selection for edge trigger mode. No change to the hardware is needed.

B.B.

[ian]

I'm sorry, so far I have not been able to reproduce the bug here. You are running through a hub, which has caused some issues in the past, does it also happen consistently without the hub?

[gotchalt]

Hi folks,
any progress concerning that topic?

got my OLS yesterday from Watterott and I am also struck with that issue.

I'm running W7-64-Ultimate,
PIC FW is 3.0
FPGA is 3.07-demon

I can do several captures but then the status bar also shows "...no such port found"

the device itsef is present in the device manager and vanishes if OLS is unplugged (and of course reappers on replug)

no way out, the machine has to be rebooted to solve the problem

Does someone have an Idea?
BoB

[ian]

Hi gotchalt,

I'm sorry about the problem. I'm running the exact same system and have never had an issue. Are you using a hub by any chance? USB 3.0 port?

After the error, can you close the OLS client, and then open a serial terminal to the COM port? This would let us know if it is a system or Java related error.

[gotchalt]

Good morning...

I tried out several things.
First of all, the COM-Port keeps "blocked by another application", as my Terminal-Program tells me...

I found out how to bring the whole situation up: start a capture and select cancel capture while waiting for trigger-event. The status bar still displays, "Capturing...".

A restart of capture usually brings up that type of error: "No such port"

I suppose that the Problem is the Windows driver for USB-PIC interfacing.

Any help appreciated

Greetz
BoB