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Having trouble installing a piece of hardware? Want to know if that peripheral is compatible with Linux?
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I've been fighting a USB > serial converter on a Debian Stretch machine
dmseg confirms the adapter is connected to /dev/ttyUSB0 and I can
connect (via minicom) to it no problem. However, it only seems to
work on incoming data but won't send anything out
For example:
cat /dev/ttyUSB0 reads data coming in just fine but echo "test" >
/dev/ttyUSB0 doesn't send anything out
While I have used the pl2303 adapters for many years without problems I've not use them with the latest distributions / kernels. I assume that you have tested the cable with ttyS0 and if you have tested the usb serial adapter with an older version and it works then the problem may lie with debian 9, the kernel with the pl2303 driver.
I tried a different converter I forgot I had (FTDI based) and it works just fine. So perhaps you're correct about the kernel. Or that the same affliction that affects Prolific-based units under Windows (counterfeit chips and/or drivers) ultimately affects Linux drivers as well...
I tried a different converter I forgot I had (FTDI based) and it works just fine. So perhaps you're correct about the kernel. Or that the same affliction that affects Prolific-based units under Windows (counterfeit chips and/or drivers) ultimately affects Linux drivers as well...
Check permissions on the /dev/tty* devices. If you can read but can't write, that would indicate your user ID/device can't be written to. Do an ls -l on /dev/ttyUSB*, and see what it says
Check permissions on the /dev/tty* devices. If you can read but can't write, that would indicate your user ID/device can't be written to. Do an ls -l on /dev/ttyUSB*, and see what it says
As my original post stated, permissions were not an issue (/dev/ttyUSB0 is both writable and readable by root) and I made sure root was part of group dialup "just in case".
Yes, it is possible that you have a "fake" or a PL-2303X device which is incompatible with the pl2303 driver. They look the same to the system but will not transmit data.
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