10-8
Reference
Information
Portable
PLUS
Computer
The test checks data retention by storing
D's
at all addresses, waiting 4 seconds,
then
reading from
alladdresses. This cycle
is
repeated using
l's
.
The test checks internal addressing of
the
RAM les
by
repeating a read-store cycle four times, using
D's
(then
l's)
and
working from low to high addresses (then from high to low). The test
further
checks the
internal addressing
by
storing at each address
the
lower eight bits of that address,
then
reading
them
back; it then repeats this cycle using the
upper
eight bits of the address.
10.3.5
LCD Test
The LCD test checks
the
LCD controller registers by writing to
and
reading from them.
The test checks
the
LCD controller
and
display module using messages
and
visual
patterns.
The visual
test includes scrolling (in alpha
and
graphics modes), border lines, horizontal
and
vertical lines, blink-
ing
and
inverse characters, xx-
and
yy-line alpha displays,
and
dual cursors.
The test checks the display RAM using all of the
RAM
tests described above for the RAM test. While
this test is executing, the display reflects
the
patterns caused by the bytes stored
in
display RAM.
10.3.6
Keyboard Test
The keyboard test displays the keyboard layout derived from the configuration EPROM
and
prompts
the
operator to press each key sequence. The test provides no key roll-over (unlike
normal
keyboard
operation). As each key is pressed, the test checks the operation of the interrupt register,
row/column
registers,
and
the debounce function in
the
multi-controller.
10.3.7
HP-IL Test
The HP-IL test checks operation of the HP-lL interface. This includes internal functions
of
the
HP-IL
controller IC, the interrupt line from the HP-IL IC,
and
the continuity of the HP-IL loop from
the
HP-
IL
OUT receptacle
to
the HP-IL IN receptacle.
The test may
be
run
with or without HP-IL peripherals connected to
the
computer.
If
no
peripherals
are connected to
the
computer, connect
an
HP-IL cable from the OUT receptacle to the
IN
receptacle.
If
one
or more peripherals are connected, make sure all are
turned
on, otherwise a "Broken Loop"
message will
appear
when
the HP-IL test is run.
To Next Page
Loading...
