Re: Raspberry Pi 3B USB Printing Issue

On 3/9/22 18:55, Archimedes Gaviola wrote:
> Hi,
> 
> I have an Epson printer connected to one of the USB ports of my RPi 3B. The
> printer is detected as a ugen(4) driver and then I have a text file -
> myfile3.txt which contains 10 lines of repeating sentences.
> 
> freebsd@generic:~ % dmesg | grep EPSON
> ugen1.4: <EPSON EPSON UB-U03II> at usbus1
> 
> freebsd@generic:~ % cat myfile3.txt
> The quick brown fox jumps over the lazy dog.
> The quick brown fox jumps over the lazy dog.
> The quick brown fox jumps over the lazy dog.
> The quick brown fox jumps over the lazy dog.
> The quick brown fox jumps over the lazy dog.
> The quick brown fox jumps over the lazy dog.
> The quick brown fox jumps over the lazy dog.
> The quick brown fox jumps over the lazy dog.
> The quick brown fox jumps over the lazy dog.
> The quick brown fox jumps over the lazy dog.
> 
> freebsd@generic:~ % cat myfile3.txt  > /dev/usb/1.4.1
> 
> I print the file successfully through device file redirection with cat
> command as described above. However, there were times that printing seemed
> to suspend and withhold especially when my RPi 3B system got idle for some
> period of time. Suspended or withhold in such a way that out of the 10
> lines there were only 2-3 lines to be printed in the paper. So, the only
> remedy I have for now is to reboot the system to be able to get back to
> normal printing. I'm using the 14.0-CURRENT #0 main-n253384-45c23c2608e:
> Thu Feb 24 09:18:58 UTC 2022 and my RPi 4B does not manifest this behavior
> using this same 14.0-CURRENT version. Any idea what's going on?
> 
> I found these sysctl knobs thinking if some tweaks would help but not sure
> what are the exact settings beyond these defaults.
> 
> hw.usb.timings.port_resume_delay: 40
> hw.usb.timings.port_powerup_delay: 300
> hw.usb.timings.port_reset_recovery: 10
> hw.usb.timings.port_root_reset_delay: 200
> hw.usb.timings.port_reset_delay: 50
> 
> (Resend this message without dmesg and sysctl outputs as files are quite
> big, sorry I didn't notice it.)
> 

Hi,

Why are you not using /dev/ulpt<N> ?

/dev/usb/1.4.1 is the raw BULK endpoint.

--HPS