Console Control Through A User-Defined Function - IBM 5110 User Manual

CONSOLE CONTROL THROUGH A USER-DEFINED FUNCTION
The
Dee
system function, like any other system function, can be
executed from a user-defined function. This technique allows the
following console control operations to be initiated from a
user-defined function:
• Turn the display screen on or off.
• Sound the audible alarm.
• Set the keyboard input to standard APL characters or lowercase
alphabetic characters.
• Scroll the display screen up or down.
• Set the left tab position for printed output (see
Printer Control
for
more information on setting the left tab position).
Following is an example of initiating console control operations from a
user-defined function:
\'J
[:I.]
[2]
[:'5::1
[1+::1
I::
~::j::l
[I.>]
[7::1
I::B]
[9::1
1:::1. 0::1
1:::1.:1. ::I
[:1.2]
[:1.3::1
I:: :I.I.f,]
1:::1.
~.:;]
I::
:1.1:.')]
[:1.7]
'i,l
Scroll the display screen up 16 lines.
'\lCONT ROL I:: [1::1 W
(~DNTI~~~L~; NA~·iE.: BTi~TE~'iENT.:
Rljset the keyboard input to lowercase
I·<~··I·I·
LlCC :I. 6 . alphabetic character mode.
R
~., ~'3
[ICC l _ I I - - - - - - - - J
· ENTE
I~
YDU R F
I
I~BT
tlND
Lf~BT N(.~i'·iE·
Ni~t'iE
f·[']
F<~"3
[ICC 0 -.. - - - - - - - - - Set the keyboard input to standard
R
~.,I.j.
[]
c
C :I. 0 AP L character mode.
e]i" 'I.JEI...CntIjE '
e]i-Nf~ME
' I
ENTER A STATEMENT TO BE EXECUTED.'
I~
(_.
I.,.
I]
C C
;.:.~
BTATEt'lENT ~ .. [']
RE ..
I+
[ICC ~?
-"Turn the display screen off to improve
r~i··:I.
nec
0- .. ------.......-'/
I~E"
.f.
BTi~~TE,\.IENT
internal performance when the next
~THE
RESULT IS: · \
statement is ,executed.
R~"2
[ICC 2 2 2 2 \
The display screen is turned on again when
output is sent to the display screen.
' " - - - - - Sound the audible alarm when the user-defined
function has completed execution.
Console Control 65