ProSoft Technology MVI56-BAS - Manual (Page 34)

BASIC Programming MVI56-BAS ♦ ControlLogix Platform
User Manual BASIC Module (DB/BAS Compatible)
Page 34 of 234 ProSoft Technology, Inc.
December 13, 2011
3.1 The Argument Stack
The results of all BASIC expressions or operations are stored in the argument
stack. The argument stack holds up to 20 values.
In order to insert a value in the top of the argument stack, the
PUSH
command
must be used.
In order to retrieve the value from the top of the argument stack, a
POP
command
must be used. It will remove the current value from the top of the argument stack
moving the following value in its place.
For example, entering in the program port command line:
>PUSH 1
>PUSH 2
>PUSH 3
>POP A
>POP B
>POP C
>PRINT A
3
>PRINT B
2
>PRINT C
1
Use CALL 109 to print the first 9 values in the argument stack to aid in
troubleshooting.
For example:
>PUSH 1
>PUSH 2
>PUSH 3
>CALL 109
000 1
001 2
002 3
Argument Stack Pointer is 3