[cups] Multiple instances of same printer (Dymo LabelWriter 450) not working

[Paul L Daniels - Personal]

Hello all,

     Ubuntu 19.10 and 20.04 with dymo drivers installed from apt

     Single dymo label printer works fine / as expected.

     Unfortunately, on installing a second printer of the same type, 
only one is ever available/detected by cups.

     I have set up udev rules to assign the printers to different ports 
based on the serial number to no avail.

     cups only ever reports the single printer DeviceURI when attempting 
to add new printers via the localhost:631 portal, and what at first 
seems to be a serial number is actually an ieee1278 device ID it rather 
seems, instead of using the printers device serial number.

Description:    DYMO LabelWriter 450
Driver:    DYMO LabelWriter 450 (grayscale)
Connection: usb://DYMO/LabelWriter%20450?serial=01010112345600

pld at WorkstationTT:~/Downloads/dymo-cups-drivers-master$ lpstat -v
device for DYMO-ADDR: usb://DYMO/LabelWriter%20450?serial=01010112345600
device for DYMO-JOBS: usb://DYMO/LabelWriter%20450?serial=01010112345600

     pld at WorkstationTT:~/Downloads/dymo-cups-drivers-master$ cat 
/etc/udev/rules.d/10-dymo.rules
SUBSYSTEMS=="usb", SUBSYSTEM=="usbmisc", ATTRS{idProduct}=="0020", 
ATTRS{idVendor}=="0922", ATTRS{serial}=="19061300590791", 
SYMLINK+="usb/dymo_jobs"
SUBSYSTEMS=="usb", SUBSYSTEM=="usbmisc", ATTRS{idProduct}=="0020", 
ATTRS{idVendor}=="0922", ATTRS{serial}=="19091715321065", 
SYMLINK+="usb/dymo_addr"

     Hoping someone can assist.  Happy to dig in to C code if required, 
but hoping that there might be perhaps an additional parameter I can use 
in the DeviceURI field to make cups differentiate between the two printers.

Regards,

Paul.



-- 
Paul L Daniels - http://pldaniels.com
A.B.N. 19 500 721 806