Hardware Reference
In-Depth Information
Event: time 1378951053.773456, -------------- SYN_REPORT ------------
Event: time 1378951053.826439, type 1 (EV_KEY), code 330 (BTN_TOUCH), value
0
Event: time 1378951053.826456, -------------- SYN_REPORT ------------
This is a single touch (
BTN_TOUCH
), but you can see it gets three distinct X (
ABS_X
) and
Y (
ABS_Y
) measurements. To determine the minimum and maximum X and Y calibra-
tion values, you will need to touch the upper-left, upper-right, lower-left, and lower-
right corners of the screen (as close to the edge as you can). Then, write down the
smallest and largest values for
ABS_X
and
ABS_Y
that appear in the
evtest
output. These
make up the values that go into your xorg config file, with this option syntax:
Option "Calibration" "<MIN_X> <MAX_X> <MIN_Y> <MAX_Y>"
Substitute in your discovered values for
<MIN_X>
,
<MAX_X>
,
<MIN_Y>
, and
<MAX_Y>
.
With your
xorg.conf.mimo
complete, you can now make the Mimo touchscreen into
your primary device by copying it to
/etc/X11/xorg.conf
as root:
$ sudo cp -a xorg.conf.mimo /etc/X11/xorg.conf
When you reboot (assuming that your Linux instance is configured to boot into a
graphical mode), you should see your desktop display out to your Mimo touchscreen.
Keep in mind that if you have something connected to the “normal” video output of
the Raspberry Pi (e.g., HDMI), you will still see the Linux kernel and boot messages go
to that device, because the DisplayLink device is not the main target for that output.
Also, because it is not using the VideoCore GPU at all, you will not be able to playback
videos using the hardware video codecs, and they will be
slow
.
Emulate Classic Video Game Consoles
HACK 51
Relive the golden era of home video gaming by letting your Raspberry Pi
pretend to be the gaming systems of yesteryear. Hey, you kids, get off
our lawn. We're hacking here!
We both have fond memories of the original Nintendo Entertainment System (NES).
(For Tom, it was his first dedicated gaming console. Ruth was still playing with an Atari
2600 and stuck with whatever could be found on 5.25-inch floppies.) Now, although
we both have kids who think of video games as something much more complicated
than
Duck Hunt
could have dreamed to be, those old 8-bit (and later, 16-bit) games
still have a lot of play left in them.
It's not surprising to see the retro trend in a lot of new independent video games, but
what about going straight to the source? Those old games from the 1980s and 1990s
were good enough for us then. We're certainly not too good for them now. You could
spend a lot of money buying a working system and all of your old games on eBay, but
