Fluke 9000A-Z80QT, Инструкция по эксплуатации

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ZBOQT
3-7.
Bit Assignment
-
Control
Lines
There are two troubleshooting functions which require the entry
of
binary digits
to identify user—writable
control lines. These functions are write control and data
toggle control.
When performing or
programming either of these two
functions, the user is
prompted
for a binary
number
to identify the
control
1ine(s)
to
be written,
BUSAK or HALT. Table
3—2
shows
that
these lines are assigned to bit numbers
0
and
1
respectively. To perform a write control
operation
on these two
lines,
enter
any of the following four bit configurations
in
response to the prompt.
As
with
the status lines, bit number 0 is at the far right of the display.
00
writes both lines low
01
writes
m
high and
m
low
10
writes BUSAK low and
H—ALT
high
11
writes both lines high
If any control
line cannot be driven, the 9000 Series mainframe responds
with the message CTRL
ERR
@
xxxxxxxx LOOP?, where x equals abinary
I
if
that
line cannot
be
driven.
For
example, if in the write
control
operation, the
HALT line can be
driven, but
the
BUSAK line
cannot,
the
9000
Series
mainframe displays the message
CTRL ERR
@
00000001 LOOP?. The BUSAK
line is
represented by bit number
0.
(A 9100 series mainframe displays
a message
in English
that
a control line
cannot
be driven.)
When performing a BUS TEST and various other mainframe operations, the
9000 Series mainframe message CTL ERR
xxxxxxxx-LOOP?
can occur, where
x represents a binary number
that
identifies which lines can
or cannot be
driven.
A binary 0
represents the ability to drive a line, while a binary
1
represents the
inability to drive
a
line. Table
3-2
lists all control lines and their
respective bit
numbers.
3-8. Address Space Assignment
The 280 is
capable
of
addressing up to 65,536 memory
locations
and up to
65,536 I/
0
locations. The mainframe uses a consistent technique
of
addressing
multiple memory and
[/0
locations.
In order
to access one
of
the 65,536 memory locations, the user provides a
hexadecimal
address in the range of 0000 to
FFFF. In order
to access one of the
l/
0
locations, the user provides a hexadecimal address in the range of 10000 to
lFFFF.
For
convenience, these assignments are also summarized on the pod
decal