Rockwell Automation 2708-DH5B2L_DH5B4L Attended Workstation - Manual (Page 91)

an A-B VBASIC Program
Chapter 10
Developing and Running
10–5
All errors encountered by the A-B VBASIC pseudo-code interpreter are
serious enough to result in the termination of the application program.
Program termination results in the following:
1. A return to the display of workstation status information (10
operator-selectable status displays discussed in Chapter 4.
2. An error message is sent through the network to the Host which begins
with the words “BASIC ERROR”.
3. The error message is also available on the BASIC run-time status display
(number 8), and through the read-only menu.
4. The diagnostic command < E will return the error message on demand
(refer to Chapter 8).
5. The error flag E is posted over the 8 on the summary status display
(number 0).
Format of a BASIC Error Message
The format of a BASIC run-time error message is:
text offset date time
where “text” is an explanation of the error,
and “offset” is the displacement from the start of the program’s pseudo code
of the pseudo-instruction which was unable to complete. The corresponding
BASIC statement can be found by correlating this value with the offset
information provided in the program listing (.LST File) from LXB. The
following chapter discusses how to get a listing file from LXB.
“date time” is the date and time the error occurred in the same form returned
by the DATE$ and TIME$ functions. Example:
0101000600BASIC ERROR: New Program Load 054B: 9102281345
Runtime error messages presented to the Host computer are preceded with
the customary 10 digit prefix, digits 9 and 10 of which are 00, followed by
BASIC ERROR (refer to Chapter 8).
A-B VBASIC
Run-Time Errors