USB Logic Analyzer: Pulseview "fx2lafw: Failed to open potential device"

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1

I’m having difficulties connecting the logic analyzer to Pulseview. After using Zadig to update the driver, Pulseview does detect it as “Saleae Logic with 8 Channels.” When attempting to connect to it, it says “Failed to open device.” You can find more verbose logging below.

I’ve tried the solutions suggested in this forum post: https://forum.sparkfun.com/viewtopic.ph … ic#p226154, but replacing the firmware files with the new downloads did not seem to have any effect.

Here is the error message I receive on startup and after trying to connect to the device:

SyntaxError: Failed to load decoder signature: import by name failed: invalid syntax (pd.py, line 138)

srd: Traceback (most recent call last):

srd: File “C:\Program Files (x86)\sigrok\PulseView\share\libsigrokdecode\decoders\signature_init_.py”, line 25, in

srd: from .pd import Decoder

srd: File “C:\Program Files (x86)\sigrok\PulseView\share\libsigrokdecode\decoders\signature\pd.py”, line 138

srd: incoming = (bin(shiftreg & 0b0000_0010_1001_0001).count(‘1’) + data) & 1

srd: ^

SyntaxError: invalid syntax

SyntaxError: Failed to load decoder signature: import by name failed: invalid syntax (pd.py, line 138)

srd: Traceback (most recent call last):

srd: File “C:\Program Files (x86)\sigrok\PulseView\share\libsigrokdecode\decoders\signature_init_.py”, line 25, in

srd: from .pd import Decoder

srd: File “C:\Program Files (x86)\sigrok\PulseView\share\libsigrokdecode\decoders\signature\pd.py”, line 138

srd: incoming = (bin(shiftreg & 0b0000_0010_1001_0001).count(‘1’) + data) & 1

srd: ^

SyntaxError: invalid syntax

fx2lafw: Failed to open potential device with VID:PID 0925:3881: LIBUSB_ERROR_NOT_SUPPORTED.

fx2lafw: Failed to open device: LIBUSB_ERROR_NOT_SUPPORTED.

sr: fx2lafw: Unable to open device.

Notifying user of session error: “generic/unspecified error”

2

Try the methods in these just to be certain:

https://www.eevblog.com/forum/beginners … -drivers)/ - comment #9 seems like the root cause? Try the steps there, different port, etc

https://learn.sparkfun.com/tutorials/us … ew/discuss

https://sigrok.org/bugzilla/show_bug.cgi?id=1152

If those don’t work it is likely defective - file for a replacement if none of those work :wink:

3

Was this ever resolved or replaced? I’m having a similar error (Failed to open Device, generic/unspecified error) with a brand new fx2la from SparkFun.

I originally tried installing it on Linux, but could not get it to open in PV. After hours of troubleshooting, confirming driver locations and udev rules, I eventually have up and switched to Windows 10 laptop. Unfortunately not having any better luck.

After initially plugging in the device and installing the Zadig drivers, going to Pulse View and connect to Device, fx2lagw (generic…), USB, scan, I hear Windows indicate a USB disconnect/reconnect and the Device shows up in the box “Saleae Logic with 8 channels”.

However, from here, no combination of reinstalling Zadig drivers or simply selecting Ok send to work.

Detailed PV log show the frontage file found, uploaded 4096 bytes, then uploaded 4024 bytes, a few more lines, then “Device failed to renumerate”.

At this point Device manager shows the Unknown Device #1 with status “this Device cannot start, an invalid parameter was passed to a service or function”.

I think I’ve been through all the t shooting suggestions linked here, plus several others I found in Google, but cannot get past this.

Can you provide any further support?

Thanks!