Acecad Acecat USB Flair Tablet in Linux

This page is to help people get their Acecat USB Flair Tablets working in Linux and with the Gimp in XFree86 4.x.

Driver

Edouard Tisserant has written a good driver for this tablet, available from this page. Here are local copies of the files (perhaps out-of-date): acecad_3.0.tgz (53.0k), README (5.5k), but check his site first.

Last I checked (quite a while ago), it was integrated into the XFree86 tree but not built by default. I'm not using the latest X sources, so I don't know what the situation is now.

For now, I'll simply recommend you to download the package and follow the instructions inside. There are actually two drivers in the package: a kernel driver, and an XFree86 driver, so even if you have a recent X sources, you probably need to get it for the kernel driver.

Installation

The following only describes my experiences of the installation process. Read the instructions.

Compiling the kernel driver was fairly straightforward. I wasn't able to get the driver working with a highly patched kernel, so I reverted to a stock kernel. For the record, it worked smoothly with 2.4.18.

Compiling the XFree86 driver was not so straightforward. The instructions suggest rebuilding the entire X tree, but I took a shortcut, which is described briefly below. If you're not sure what you're doing, I don't suggest you try to reproduce it. It's really just for me, so I can do it again when I upgrade my system.

  1. After unpacking the X sources, xc/programs/Xserver/hw/xfree86/input/acecad contained an older driver, so I replaced those files with Edouard's X driver.
  2. I edited the Makefile so that all the directories in the entire X source tree were specified as include directories for gcc, i.e. one huge list of -Idir1 -Idir2 -Idir3 ... (No, I didn't do it by hand ;-)
  3. Then make. The driver compiled okay (not the first time, of course), but there was some problem the makefile script later on. I ignored that.
  4. Then I copied the acecad_drv.o into /usr/X11R6/lib/modules/input and modified XF86Config.

Configuring XF86Config

Read the instructions ;-) In case it helps, here's my XF86Config (13.6k) file, only a few lines of which are relevant.

Pitfalls

These are a couple of problems I came across when trying to get everything to work. (Actually, this section is the reason for this page.)


I can move my cursor with the pen, but there is no pressure information in the Gimp, and the Input Devices Dialog shows "No Input Devices".

You probably need to recompile your GTK/GDK with XInput support. Rebuild GTK/GDK using ./configure --with-xinput=xfree. You may or may not need to rebuild your copy of the Gimp (I didn't).


The Gimp recognises my tablet, but when I try to draw with it, the Gimp doesn't draw where the X cursor is, or where I expect it to.

If you have set the "AlwaysCore" option for the tablet in XF86Config, i.e. you are able to control the X cursor with the tablet as well as a mouse, then you should choose the "Screen" mode in the Input Devices Dialog in the Gimp.

If that doesn't work, or you didn't set the "AlwaysCore" option, perhaps you did what I did. I have a USB mouse on the same system, and my XF86Config section for the mouse looked like this:

Section "InputDevice"
    Identifier  "Mouse1"
    Driver  "mouse"
    Option "Device"      "/dev/input/mice"
      .
      .

The culprit was the /dev/input/mice line. As I understand it, that device file collects input for all the mouse-like devices handled by the kernel, including the tablet. So when I started using the tablet, X was not only getting input from the tablet, but it also thought I was moving the mouse, too. Hence the mouse cursor was moving twice as fast as it should have when I used the tablet.

The fix for this is to simply to use a specific /dev/input/eventn device file instead of /dev/input/mice. You have to find what that n is, of course (do cat /dev/input/eventn and move either the mouse or the pen to see which one generates garbage output on your screen).

Related

Wacom Tablet HOWTO -- more information about tablet usage


Peter Wang

Last update: 2002-10-04