Vidicode Argus Basic Programmers Reference Manual

ARGUS Programmable Modem 
BASIC Programmers Reference Manual 
© 1990 - 1997 Vidicode Datacommunicatie BV 
108
  
LEFT$    extract left part of a string 
LEFT$ extracts the specified number of characters from the left-hand side of a string.  The command: 
L$=LEFT$(ABCDEFGH,3)
will assign the string ABC to the string variable A$. 
 
The number of characters extracted must be between 0 and 255.  Attempts to extract more characters than exist in the string 
will return the entire string. 
Examples:...

ARGUS Programmable Modem 
BASIC Programmers Reference Manual 
© 1990 - 1997 Vidicode Datacommunicatie BV 
109
  
LEN    get length of string 
LEN returns the length of the specified string, including spaces and non-printing characters. 
Examples: 
Size=LEN(Name$)
IF LEN(Name$) >30 THEN PRINT Name too long ..
PRINT LEN(Message$)
Syntax: 
[num-var] = LEN( [string] )
See also: 
LEFT$, MID$, RIGHT$
  

ARGUS Programmable Modem 
BASIC Programmers Reference Manual 
© 1990 - 1997 Vidicode Datacommunicatie BV 
110
  
LENGTH    set or read serial port word length 
The LENGTH function is used to set or read the number of data bits used during serial data transfer. 
 
The number of bits used can be specified separately for each port, and may be set to 7 or 8 bits.  The most common format 
for ASCII systems is 8 data bits, no parity and 1 stop bit, which is the default format used by this modem.  This format...

ARGUS Programmable Modem 
BASIC Programmers Reference Manual 
© 1990 - 1997 Vidicode Datacommunicatie BV 
111
  
LINEFEED    enable/disable Line Feeds 
Most terminals and printers accept a combination of Carriage Return (ASCII 13) and Line Feed (ASCII 10) characters to 
indicate the end of a line, while others require only a Carriage Return, and insert a Line Feed automatically.  The 
LINEFEED command is used to switch Line Feeds on or off, as appropriate. 
 
LINEFEED ON causes the modem to insert a Line...

ARGUS Programmable Modem 
BASIC Programmers Reference Manual 
© 1990 - 1997 Vidicode Datacommunicatie BV 
112
  
LINK    connect logical data streams 
LINK is used to create transparent links between two serial ports. 
The advantage of linking ports can be explained with the following example. 
 
Assume that a terminal is connected to port 1, and a computer to port 2, and that both are set for 9600 baud operation.  
There are various ways of connecting the two devices.  The first is to write a program...

ARGUS Programmable Modem 
BASIC Programmers Reference Manual 
© 1990 - 1997 Vidicode Datacommunicatie BV 
113
  
20 LINK#2,#1
30 HANDSHAKE#1 LINK ON
40 HANDSHAKE#2 LINK OFF
50 MATCH#1, PASSWORD
60 ...
Note that the first port number specified in the LINK command is that of the input port.  One or more output ports then 
follow: 
LINK#1,#2,#7
Here port 1 is the input port; ports 2 and 7 are outputs. 
 
The following will create a bi-directional link between ports 2 and 3 while allowing port 1 to monitor...

ARGUS Programmable Modem 
BASIC Programmers Reference Manual 
© 1990 - 1997 Vidicode Datacommunicatie BV 
114
  
  

ARGUS Programmable Modem 
BASIC Programmers Reference Manual 
© 1990 - 1997 Vidicode Datacommunicatie BV 
115
  
LIST    list BASIC program 
LIST is used to list the currently loaded program to the specified port. 
 
When used without a parameter, the entire program will be listed to the default output port as defined by OPORT. 
 
A range of line numbers can be specified; thus the following example will only list those lines from 500 to 1000 inclusive: 
LIST 500,1000
To list from the start of the program...

ARGUS Programmable Modem 
BASIC Programmers Reference Manual 
© 1990 - 1997 Vidicode Datacommunicatie BV 
116
  
LIST AUTO    list program for editing 
This is used to capture a special listed program for editing. 
 
This command lists programs without line numbers included.  Programs captured in this way can be edited offline and ASCII 
uploaded back to the modem using the AUTO command. 
 
When performing an ASCII upload to the modem, the AUTO command will automatically assign numbers to program lines....

ARGUS Programmable Modem 
BASIC Programmers Reference Manual 
© 1990 - 1997 Vidicode Datacommunicatie BV 
117
  
LOAD    load BASIC program or data 
The principal use of LOAD is to copy programs from disk into program memory, at the location specified by the system 
variable PBOT. 
 
To load from the disk, use LOAD (followed by an optional exclamation mark) and the filename within double quotes: 
LOAD DIAL.PROG
By changing the value of PBOT it is possible to LOAD a number of programs into memory at once:...