Master branch works with -s /dev/ttyUSB0 but fails with -s /dev/serial/by-id/<long Sonoff name>

[jsmif]

Master branch works with -s /dev/ttyUSB0 but fails with -s /dev/serial/by-id/

from sniffle.

[sultanqasim]

Strange, I’m not sure why that happens. Could you try a previously tagged release instead of the current master branch to see if the same thing occurs? I’m away from my computer at the moment but I can try later when I have a chance.

[jsmif]

OK, I tried the 1.10.0 and 1.9.3 tags, but they actually exhibit the same behavior. I thought it was perhaps the OS being an issue since I'm using Ubuntu 24.04 and the known-working-with-long-form host is Ubuntu 22.04. But no, I have a separate Ubuntu 22.04 VM which I could try on, and on that too both master and those two tags work for the short form and fail for the long form.

FWIW both

sudo screen /dev/ttyUSB0 921600

and

sudo screen /dev/serial/by-id/usb-ITead_Sonoff_Zigbee_3.0_USB_Dongle_Plus_55ca6286e3e4f4fba5d0448333fa99fc-if00-port0 921600

Show valid well-formed base64 data, and I was using a dongle specifically reflashed to the "1M" sonoff firmware so I could just test the default behavior with no changes to the sniffle_hw.py.

So I went and grabbed the dongle from the Ubuntu 22.04 system where the long form works. The box is at commit 01e064b. The dongle is running the 2M firmware with the following diff (because I don't know which case is the one I should change away from 921600)

--- a/python_cli/sniffle/sniffle_hw.py
+++ b/python_cli/sniffle/sniffle_hw.py
@@ -97,9 +97,11 @@ class SniffleHW:
                 if serport is None:
                     raise IOError("Sniffle device not found")
                 else:
-                    baud = 921600
+#                    baud = 921600
+                    baud = 2000000
         elif is_cp2102(serport):
-            baud = 921600
+#            baud = 921600
+            baud = 2000000

When I then check out that commit, and make that change, the Ubuntu 22.04 VM works with the long form of the serial path fine.

[sultanqasim]

Ah, that gives me a good pointer to what's happening. The is_cp2102 function will return False if the supplied serial port path is not the canonical path to the dongle (i.e. /dev/ttyUSB0). Is /dev/serial/by-id/usb-ITead_Sonoff_Zigbee_3.0_USB_Dongle_Plus_55ca6286e3e4f4fba5d0448333fa99fc-if00-port0 a symlink to /dev/ttyUSB0? If so, I can change the code to follow symlinks.

[jsmif]

Yep, it's a symlink

[sultanqasim]

Try now with (with bf91946)

[jsmif]

Yep, works now. Thanks!