EasyManuals Logo

IBM 7090 User Manual

IBM 7090
190 pages
To Next Page IconTo Next Page
To Next Page IconTo Next Page
To Previous Page IconTo Previous Page
To Previous Page IconTo Previous Page
Page #11 background imageLoading...
Page #11 background image
The
program
for
this
problem
is
made
up of
instructions
and
data
channel
commands
that
control
the
7090
to
perform
the
operations
outlined.
These
instructions
and
com-
mands
progress
step-by-step
and
the
control
section
recognizes
each
in
turn
when
the
previous
operation
is
complete.
Because
the
control
section
of
the
system
operates
at
electronic
speed
and
the
card
reader
and
printer
are
relatively
slow,
it
is
apparent
that
much
communication
is
nec-
essary
between
the
mechanical
functions
and
the
control
section.
The
control
section
must
wait
until
A
and
B
have
been
read
from
the
card
before
adding
them
together.
The
sum
C
can
be
developed
and
stored
at
electronic
speed,
but
must
wait
in
storage
until
the
printer
is
ready
to
receive
it
for
printing.
Figure
1.
4-1
shows
the
progression
of
the
steps
in
the
foregoing
program.
Not
shown
in
Figure
1.4-1
are
the
instructions
and
commands
that
initiate
each
of
the
oper-
ations
depicted.
These
are
also
in
storage
along
with
the
factors
A
and
B
and
constitute
the
stored
program.
As
each
instruction
ends
its
operation,
the
next
instruction
is
called
out
and
initiates
its
operation.
In
this
manner,
the
7090
system
progresses
through
the
solution
according
to
the
program
in
storage.
1.
4.01
The
Stored
Program
The
program
previously
described
used
CPU
instructions
and
data
channel
commands
from
storage.
These
instructions
controlled
other
information
going
to
and
from
stor-
age.
But
how
did
the
instructions
and
commands
get
into
storage?
In
the
beginning,
the
author
of
the
program
decides
what
instructions
and
commands
to
use
and
in
what
order
to
use
them.
There
are
several
ways
to
get
these
instructions
and
commands
in-
to
storage
without
a
stored
program
already
in
the
system.
Among
these
ways
are
direct
manual
entry
from
the
operator's
keys
on
the
IBM 7151
Console
Control
Unit *,
entry
from
cards
or
tape
caused
by
a
command
manually
entered
into
a
data
channel
from
the
IBM 7617
Data
Channel
Console
*,
and
forced
automatic
operation
of a
card
reader
or
tape
unit
caused
by
depression
of a
load
key
on
the
CPU
console.
\Vh.atever
the
means
of
entry,
both
the
stored
program
instructions
and
the
data
to
be
processed
must
be
previously
translated
into
machine
language
in
the
form
of
binary
words.
A
binary
word,
as
used
in
the
7090,
consists
of 36
binary
positions.
The
bin-
ary
number
system
is
explained
in
Appendix
A
of
IBM 7090
Data
Processing
System
Reference
Manual,
Form
A22-6528.
Also
explained
there
are
processes
for
conversion
of
decimal
numbers
to
binary
numbers,
and
binary
numbers
to
decimal
numbers.
A
third
system
(called
octal)
provides
a
quicker
and
less
cumbersome
means
of
expressing
binary
numbers.
1.
4.
02
Exercises
The
following
equivalent
numbers
in
binary,
octal,
and
decimal
provide
an
opportun-
ity
to
practice
conversion
from
one
number
system
to
another.
Do
the
conversions
and
check
your
results
against
those
given.
(Decimal
and
octal
fractions
are
rounded
to
three
places
and
binary
fractions
are
rounded
to
nine
places.)
*
The
CPU
console
(IBM
7151)
is a
separate
machine
type,
and
there
is
only
one
on
each
7090
system.
Each
7607
Data
Channel
has
a
manual
console
of
its
own
(IBM
7617).
10

Table of Contents

Questions and Answers:

Question and Answer IconNeed help?

Do you have a question about the IBM 7090 and is the answer not in the manual?

IBM 7090 Specifications

General IconGeneral
CategoryMainframe Computer
Introduced1959
Transistor-basedYes
Word Length36 bits
Add Time4.8 microseconds
MemoryCore memory
Memory (words)32, 768 words