5-2
Chapter 5: Programming
Wedge Controller Interface
Refer
to
the
Wedge
Controller
1.0
Implementation
Specification
(497
‐
0001747)
and
the
Trigantor
Device
Specification
(006
‐
8601066)
for
a
complete
description
of
the
Wedge
Controller
(Wedge)
The
Wedge
consists
of
a
microcontroller
(8051)
and
associated
logic
(including
the
Trigantor
ASIC)
which
supports
certain
devices
that
can
be
logically
connected
in
series
with
a
standard
PC
keyboard.
It
controls
input
devices
such
as
the
ISO
3
‐
track
MSR
and
keyboard
data,
and
merges
the
data
from
any
of
them
into
the
data
stream
of
a
PC
keyboard.
It
also
controls
the
operation
of
the
speaker.
Touch Screen Interface
The
touch
screen
interfaces
to
the
terminal
via
the
terminal’s
standard
RS232
port.
The
5964
LCD
uses
the
Serial/SMT3
controller
referenced
in
that
document.
There
is
a
bar
code
label
(two
‐
dimensional
PDF417
symbology)
attached
to
the
tail
of
the
touch
sensor
that
contains
the
25
point
linearization
parameters
associated
with
that
particular
touch
sensor.
This
bar
code
label
is
scanned
and
the
resulting
data
block
is
programmed
into
an
on
board
non
‐
volatile
EEPROM
on
the
5964
LCD
Display
Main
Board
during
the
manufacturing
process.
This
provides
the
touch
controller
with
course
calibration
data
prior
to
initial
system
power
‐
up.
After
the
course
calibration
data
has
been
stored,
all
that
is
required
to
calibrate
the
sensor
when
installed
on
the
LCD
is
to
run
the
two
‐
point
extended
calibration
routine.
The
extended
calibration
routine
has
the
two
touch
points
moved
inward
12.5%
from
the
corners
of
the
display
for
easier
access.
The
MicroTouch
firmware
defaults
to
the
following
communication
parameters:
