Parblo A640: UC-Logic pen pressure works once Wacom X.org driver is enabled

[hyiltiz]

A friend got this, and I wanted to try it out. The pen on the tablet acted as a mouse, but the pressure didn't work in GIMP even after the Input Device was set to Screen and the brush dynamics was set to Pressure Opacity despite evtest reported pressure values in entries like this:

Event: time 1564083030.673190, type 3 (EV_ABS), code 24 (ABS_PRESSURE), value 361

Tried installing the DIGImend dkms drivers, unloaded the drivers, unplugged the USB cable then reloaded the drivers then plugged back in. No success.

What worked is the simple Xorg.conf template on this site (including below to keep the post complete):

Section "InputClass"
    Identifier "Tablet"
    Driver "wacom"
    MatchDevicePath "/dev/input/event*"
    MatchUSBID "<VID>:<PID>"
EndSection

where <VID>:<PID> is the ID from lsusb output.

The device parameters as reported by uclogic-probe were as follows:

# lsusb
...
Bus 002 Device 002: ID 5543:0061 UC-Logic Technology Corp. A640
...
# uclogic-probe 2 2
M 55 00 43 00 2D 00 4C 00 6F 00 67 00 69 00 63 00
P 41 00 36 00 34 00 30 00
S 64 12 03 B0 73 12 43 03 00 FF 1F D8 13 0A 00 00 00 00 00
S 65 04 03 91 67
S 6E 04 03 30 00
S 79 07 03 BE FF AF 00 00
S 7A 08 03 02 04 00 54 00 00
S 7B 0C 03 48 00 4B 00 20 00 4F 00 6E 00
S C8 20 03 46 00 36 00 31 00 30 00 5F 00 4F 00 30 00 38 00 31 00 30 00 5F 00 41 00 50 00 5F 00 54 00
S C9 20 03 46 00 36 00 31 00 30 00 5F 00 4F 00 30 00 38 00 31 00 30 00 5F 00 41 00 50 00 5F 00 54 00
S CA 20 03 46 00 36 00 31 00 30 00 5F 00 4F 00 30 00 38 00 31 00 30 00 5F 00 41 00 50 00 5F 00 54 00
# uclogic-probe 2 2|uclogic-decode
    |           Manufacturer: UC-Logic
    |                Product: A640
 64 |        Params block #1: ????????
    |                          Max X: 29616
    |                          Max Y: 17170
    |                   Max pressure: 8191
    |                     Resolution: 5080
    |
 79 |         Internal model: ??
 7b |         Buttons status: HK On
 c8 |        Params block #2: F610_O0810_AP_T
    |                          Max X: 3539014
    |                          Max Y: 12544
    |                   Max pressure: 48
    |                     Resolution: 95
    |
 c9 |       Firmware version: F610_O0810_AP_T
 ca |  Internal manufacturer: F610_O0810_AP_T

Thank you so much! I even tried to "decompile" the macOS driver provided by Parblo's website as they didn't, unsurprisingly, provide any driver or instructions for GNU/Linux. Now I can play with this dirty cheap pad.

[RudyTheNinja]

What worked is the simple Xorg.conf template on this site (including below to keep the post complete):

Section "InputClass"
    Identifier "Tablet"
    Driver "wacom"
    MatchDevicePath "/dev/input/event*"
    MatchUSBID "<VID>:<PID>"
EndSection

where <VID>:<PID> is the ID from lsusb output.

Sorry but I'm kinda lost, how did you get it to work? I can get the template myself, fill it out correctly but then.. where do I put it?

Edit: I looked into it more saw the small tutorial at the front page of this project Said I needed to have X.org drivers installed (I installed using the .deb so I should of had it) Then said to find /etc/X11/xorg.conf.d/50-tablet.conf but there was no xorg.conf.d folder

I did a full search for it and it ended up being in my usr/shared/... area instead And there was no 50-tablet.conf file there, only a 50-digimend.conf file When attempting to alter anything there it would then say that I wasn't the owner and did not have the perms Had to do sudo gedit to alter the file

My goal was to finally have pressure sense but it didn't help achieve that, it made the tablet less responsive instead with the ability to hover suddenly disabled. It would only draw when medium pressure is put on the pen

Again, what is this Xorg.conf that you say was simple?? The one I found had already had presets in it, so I just added my tablet to it:

Section "InputClass"
    Identifier "Tablet"
    Driver "wacom"
    MatchDevicePath "/dev/input/event*"
    MatchUSBID "5543:0061"
EndSection

And the filepath was nowhere as the main page of this project states

[hyiltiz]

Where what file should be saved depends on what distribution you are running, but in most it is definitely under /etc/ not /usr/, and furthermore most likely to be at this path: /etc/X11/xorg.conf.d/50-tablet.conf. You'll need sudo, then reboot your OS while the USB cable is plugged in. There is some issue if you unplug and plug back in, the whole thing stops working properly (the device is somehow only registered as general mouse but not a graphics tablet device even though wacom kernel drivers are loaded and xsetwacom list correctly lists them). So do not unplug it if you plan to use it later; or just reboot again every time you wish to use.

I wrote the report above as a Thank You note to the devs, and if they so desire and if all info provided above is enough, they can add in support to Parblo A640 by default so in newer versions of this package would include config files by default. Thus, some standard system admin tasks and know-hows were assumed, such as how to write a config file for Xorg and where to put it.

[RudyTheNinja]

I can't seem to find the xorg.conf.d folder Perhaps I'm missing something in order to have anything at that file path, any idea as to what that could be?

I installed the .deb provided here, could it be something that the driver package doesn't include?

[hyiltiz]

Simply create the parent folders whenever necessary for the file path, e.g. to write to the file /etc/X11/xorg.conf.d/50-tablet.conf, do:

mkdir -p /etc/X11/xorg.conf.d/
gedit /etc/X11/xorg.conf.d/50-tablet.conf