HP 82718A Expansion Pod Reference Manual page 47

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Software Usage and Examples
Line 10 changes the command character to !. Line 20 sends the old command character. A carriage ~,
return is not needed because data only is being sent, not a command. Line 30 changes the command
character back to
%;
if the! character is subsequently sent to the modem, it will be seen as data. Notice
that while the command character is !, it must be used in all commands, including ! N for the NEW
command on line 30. These three lines can be combined into one string for
t'10DOUT
as follows (note the
placement of the carriage returns only after each
N
command):
10 t'10DOUT
II
~·~t·~
!
II
8.:CHF.:$ ( 1:::)
:~.:
II
~.~
II
t
II
!
t·~ ~.~
II
:~.:CHF.:$
( 1:::)
An example of the use of the
U (UN
LI
STEN)
command is:
1
[1
t'10DOUT
II
~·~U
111
:~.:CHF::$
( 1 :::)
2[1
t'10DOUT
II
~.~
II
Line 10 tells the modem to treat the next 1 byte as data only-ignore any command characters in that
data. The byte at line 20 is then sent on unprocessed. No carriage return is needed on line 20 because
only data is being sent. These can be combined into one string for
t'1ODOUT
as follows:
1
[1
t'10DOUT
II
~'~U
111
:~.:CHF::$
( 1 :::) t
II
~.~
II
The use of two command characters is shown below:
10 t'10DOUT
II •..•. ' II
...•...•
To send a string containing one or more command characters (assuming there are no deliberately
embedded commands), the three approaches are applied slightly differently. The N command is used as
follows:
1
[1
P=PO::; (::;$,
II
~.~
I I )
I~
IF
P
THEt·~
t'10DOUT
II
~·~t·~
! II
:U::HF::$ (
1 :::)
20 t'10DOUT ::;$
::::0 IF
P THEt·~ t'10DOUT
I I !
t·~ ~.~
II
:~.:CHF::$ (
1 :::)
Line 10 changes the command character to ! if there are any command characters in
S$.
Line 20 sends
the data, and line 30 restores the old command character if it had been changed. This will not work, of
course, if the string contains one or more ! characters.
The
U
command is used as follows:
1
[1
I F PO::; (::;$,
II
~.~
I I )
THEt·~
t'10DOUT
II
~·~U
II
tSTF.:$
(LEt~
(S$) ) g.:CHF::$ ( 1 :::)
20 t'10DOUT S$
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