ngscopeclient
usbtmc issues
Situation: Trying to add a lecroy waverunner 9104 to ngscopeclient (compiled by user)
Error: dmesg:
[ 7492.115442] usb 2-3: new SuperSpeed USB device number 7 using xhci_hcd
[ 7492.127656] usb 2-3: config 1 interface 0 altsetting 0 endpoint 0x82 has an invalid bInterval 0, changing to 7
[ 7492.128009] usb 2-3: New USB device found, idVendor=05ff, idProduct=1023, bcdDevice= 1.00
[ 7492.128015] usb 2-3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 7492.128017] usb 2-3: Product: LeCroy oscilloscope USBTMC device
[ 7492.128020] usb 2-3: Manufacturer: LeCroy Corp (www.lecroy.com)
[ 7492.128023] usb 2-3: SerialNumber: 4703N40707
[ 7543.224945] usbtmc 2-3:1.0: send_request_dev_dep_msg_in returned -110
[ 7548.344905] usbtmc 2-3:1.0: Unable to send data, error -110
[ 7553.464980] usbtmc 2-3:1.0: send_request_dev_dep_msg_in returned -110
[ 7558.584770] usbtmc 2-3:1.0: Unable to send data, error -110
[ 7563.704652] usbtmc 2-3:1.0: send_request_dev_dep_msg_in returned -110
[ 7568.824669] usbtmc 2-3:1.0: Unable to send data, error -110
[ 7573.944442] usbtmc 2-3:1.0: Unable to send data, error -110
[ 7579.064680] usbtmc 2-3:1.0: send_request_dev_dep_msg_in returned -110
[ 7584.184383] usbtmc 2-3:1.0: Unable to send data, error -110
[ 7589.305461] usbtmc 2-3:1.0: Unable to send data, error -110
[ 7594.424524] usbtmc 2-3:1.0: Unable to send data, error -110
[ 7599.544296] usbtmc 2-3:1.0: send_request_dev_dep_msg_in returned -110
[ 7604.664365] usbtmc 2-3:1.0: Unable to send data, error -110
[ 7609.784364] usbtmc 2-3:1.0: Unable to send data, error -110
[ 7614.904332] usbtmc 2-3:1.0: send_request_dev_dep_msg_in returned -110
[ 7620.024392] usbtmc 2-3:1.0: Unable to send data, error -110
[ 7625.143874] usbtmc 2-3:1.0: send_request_dev_dep_msg_in returned -110
[ 7630.264110] usbtmc 2-3:1.0: Unable to send data, error -110
ngscopeclient:
./ngscopeclient
error: XDG_RUNTIME_DIR is invalid or not set in the environment.
Warning: Bad IDN response
Warning: Bad IDN response
Warning: Bad IDN response
ERROR: Persistent bad IDN response, giving up
ERROR: Bad IDN response
Operating system: Linux name 6.16.4-arch1-1 #1 SMP PREEMPT_DYNAMIC Thu, 28 Aug 2025 19:49:53 +0000 x86_64 GNU/Linux
This seems like it's a communications problem between the Linux USBTMC driver and the scope, not something we can fix on the ngscopeclient/libscopehal side. Not sure if it's the scope's fault or the Linux kernel driver's fault (you can poke at sniffing the USB traffic with wireshark if you really want) but USBTMC in general can be pretty buggy.
If you just want to get ngscopeclient working with your scope, I suggest using VICP over Ethernet. This should work flawlessly since it's what I use with my WaveRunner 8404M-MS and SDA 816Zi-A.
The same here with a Keysight InfiniiVision MSOX3024T on mx linux (in a VM).
When using another USB cable it starts kind of working somehow:
$ sudo ngscopeclient myscope:keysightdca:usbtmc:/dev/usbtmc0
I can set the trigger, but acquiring a waveform makes it freeze or crash. Most of the time withou any message, once with:
ERROR: Waveform preamble length (0) does not match data length (62500)Gleitkomma-Ausnahme
Any suggestion what I am doing wrong?