Powermax communications issue

CFE
Offline
Elite Member

01 Nov 2021 23:41 #224938 by CFE

Replied by CFE on topic Powermax communications issue

Hi All,

Thanks for your replies and sanity checks

I got a RS485 to USB serial adapter, as per user guide. That worked right out of the box on the previous installation and with the same plasma unit, hence I am confused why it doesn't work now. I double checked the wiring, that all is good. I do not think it is something in QtPlasmaC, I assume it has something to do with python or the way usb devices are recognized by linux. I reinstalled python-serial. but to no avail. Not sure what to do. It's such a handy feature to have !

Cheers, Peter

Please Log in or Create an account to join the conversation.

phillc54
Offline
Moderator

01 Nov 2021 23:57 #224939 by phillc54

Replied by phillc54 on topic Powermax communications issue

Seeing as how it doesn't appear in the devices list then I don't think it is a python issue, more of an OS issue.

With the device unplugged enter lsusb then plug the device in and run lsusb again. The device should be listed.

Please Log in or Create an account to join the conversation.

grijalvap
Offline
Elite Member

01 Nov 2021 23:58 #224940 by grijalvap

Replied by grijalvap on topic Powermax communications issue

Is your serial port listed?
you can check using ls /dev/ttyUSB*
then make sure the /dev/ttyUSBx devise is en the plasma c ini file
you can use putty or minicom to verify port is working, just need to make a loop from out to in the type in the putty or minicom if it is ok you should see what you are typing.

Please Log in or Create an account to join the conversation.

CFE
Offline
Elite Member

07 Nov 2021 22:51 #225596 by CFE

Replied by CFE on topic Powermax communications issue

Hi all,

I ran lsusb and the usb to serial adapter shows as :
Bus 002 Device 013: ID 0403:6001 Future Technology Devices International, Ltd FT232 Serial (UART) IC

I have removed, purged and reinstalled python3-serial, but still no response if I run PMX485-test, except a message telling me to check the connections, which I have done. The device on on the Powermax communicator screen shows /dev/ttyS0. Starting to wonder if there is something going on in the plasma unit itself ? (Although we haven't touched it, and the plasma unit is only 2 months old.)

Cheers, Peter

Please Log in or Create an account to join the conversation.

phillc54
Offline
Moderator

07 Nov 2021 23:26 #225598 by phillc54

Replied by phillc54 on topic Powermax communications issue

I really don't know what is going on.
On my PC it always shows /dev/ttyS0 as a device whether I have my USB serial adapter plugged in or not.
When I plug in my USB serial adapter and click PORT SCAN then it adds /dev/ttyUSB0 as a valid device.
Your PC doesn't seem to be adding the USB adapter as a serial device.

Please Log in or Create an account to join the conversation.

CFE
Offline
Elite Member

07 Nov 2021 23:43 #225600 by CFE

Replied by CFE on topic Powermax communications issue

Hi Phil,

Before I upgraded to the 64-bit version our system did the same as what you describe, plug the USB adapter in, PORT SCAN, it added /dev/ttyUSB0 and we were away, no worries. Now I am on the 64-bit version and it stopped working. I had a look trough the BIOS and got everything USB related set at AUTO or ENABLED, so I like to think there is no issue there. It really is such a great feature if it works !

Please Log in or Create an account to join the conversation.

phillc54
Offline
Moderator

07 Nov 2021 23:51 #225602 by phillc54

Replied by phillc54 on topic Powermax communications issue

What is the result of the last few lines if you unplug the adapter, plug it in again and enter dmesg in a terminal.

Please Log in or Create an account to join the conversation.

tommylight
Away
Moderator

08 Nov 2021 00:10 #225609 by tommylight

Replied by tommylight on topic Powermax communications issue

Also the port should be checked with
ls /dev/tty*
as USB devices have some naming issues, like ttyUSB or ttyACM or ..

Please Log in or Create an account to join the conversation.

CFE
Offline
Elite Member

08 Nov 2021 00:22 #225611 by CFE

Replied by CFE on topic Powermax communications issue

Hi all,

I ran dmesg and found the entries for the serial adapter near top end which show this :

    4.833201] usbcore: registered new interface driver ftdi_sio
[    4.834562] usbserial: USB Serial support registered for FTDI USB Serial Device
[    4.835080] ftdi_sio 2-6:1.0: FTDI USB Serial Device converter detected

I am reasonably sure that is the serial adapter, but then at the end of the dmesg output it shows this :

[    6.696746] ftdi_sio ttyUSB0: FTDI USB Serial Device converter now disconnected from ttyUSB0
[    6.696769] ftdi_sio 2-6:1.0: device disconnected

I assume that has something to do with the issue, if the serial adapter disconnects from USB. But how to solve that ?

Please Log in or Create an account to join the conversation.

phillc54
Offline
Moderator

08 Nov 2021 00:45 #225613 by phillc54

Replied by phillc54 on topic Powermax communications issue

This is what I see when I unplug my adapter:

[ 1870.592430] usb 3-2: USB disconnect, device number 7
[ 1870.592563] ch341-uart ttyUSB0: ch341-uart converter now disconnected from ttyUSB0
[ 1870.592572] ch341 3-2:1.0: device disconnected

This is what I see when I plug the adpater in again:

[ 1878.330632] usb 3-2: new full-speed USB device number 8 using xhci_hcd
[ 1878.479817] usb 3-2: New USB device found, idVendor=1a86, idProduct=7523, bcdDevice= 2.54
[ 1878.479819] usb 3-2: New USB device strings: Mfr=0, Product=2, SerialNumber=0
[ 1878.479820] usb 3-2: Product: USB2.0-Serial
[ 1878.482001] ch341 3-2:1.0: ch341-uart converter detected
[ 1878.483414] usb 3-2: ch341-uart converter now attached to ttyUSB0

So after plugging in the last line should be the attachment to ttyUSB0 or similar.

Please Log in or Create an account to join the conversation.

Moderators: snowgoer540

Time to create page: 0.100 seconds