Ormec MotionBASIC, Руководство пользователя программного обеспечения

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MotionBASIC
TM
Error Handler Modifying Your Program
routine that will put the machine back into a condition in which it can be safely
restarted. APPL.RESTART can be a special routine or simply a label in your
normal program power-up initialization code.
Before executing the GOTO APPL.RESTART statement, the error handler
executes a STACK CLEAR statement. This clears the control stack of any
subroutine RETURNs, WHILE/WEND loops and FOR/NEXT loops. Without this
statement each time an error occured any open RETURNS or loops would be
left on the stack and your program would eventually run out of memory. This
means that the APPL.RESTART label must be placed in a location in the
program where no subroutines, WHILE/WEND loops or FOR/NEXT loops are
open. Figure 5 shows the recommended location for the APPL.RESTART
label.
Figure 5, Recomended Power-Up Sequence
POWERUP:
.
.
in-line initialization code
.
GOSUB MISC.COLORS
GOSUB ERR.INIT
.
.
other MBTools initialization subroutine calls
.
ON ERROR GOTO ERR.HDLR
APPL.RESTART:
GOSUB MAIN
END
The APPL.RESTART label is located immediately after the
ON ERROR GOTO ERR.HDLR statement. If there were statements between
these two lines, a run-time error while executing one of them could cause the
remaining statements to be skipped with unpredictable results.
5.7 Invoking The Fault Menu
After completing the error trapping and shutdown routines, the Error Handler
module will automatically invoke the Fault Display Menu. If you want to call the
Fault Display when no fault has occurred, include a GOSUB ERR.MENU
statement at the appropriate point in your program. When the operator leaves
the Fault Display, the program will return to the next statement in your program.
5.8 Invoking From MENU.BAS
If you are using the MBTools MENU.BAS MMI Module to provide your man
machine interface, you can use MENU.BAS to call the Fault Menu Display
Menu. Details on how to configure MENU.BAS to do this are included in the
manual for MENU.BAS.
GN3-ERRb page 17