Rockwell Automation 1771-DB Basic Module User Manual - Series A - Manual (Page 53)

Operating Functions
Chapter 5
5–16
The
following sections list and describe the statements you can use
with the BASIC Module.
Mode:
COMMAND AND/ OR RUN
Type:
CONTROL
You
use the CALL [integer] statement to call specially written BASIC
Module application programs. Specific
call numbers are defined later
in this chapter.
Mode:
COMMAND AND/OR RUN
Type:
CONTROL
The
CLEAR statement sets all variables equal to 0 and resets all
BASIC
evoked interrupts and stacks. This means that after the CLEAR
statement is executed an ONTIME statement
must be executed before the
module acknowledges the
internal timer interrupts. ERROR trapping
using the ONE
RR statement also does not occur until an
ONERR[integer]
statement is executed. The CLEAR statement does
not affect
the real time clock that is enabled by the CLOCK1
statement.
CLEAR also does not reset the memory that has been
allocated
for strings, so it is not necessary to enter the STRING
[expr],
[expr] statement to re-allocate memory for strings after the
CLEAR
statement is executed. In general, CLEAR is used to
“erase”
all variables.
Mode:
COMMAND AND/OR RUN
Type:
CONTROL
The
CLEARI statement clears all of the BASIC evoked interrupts. The
ONTIME interrupt
disables after the CLEARI statement executes.
CLEARI does not affect
the real time clock enabled by the CLOCK1
statement. You can use this statement
to selectively DISABLE
ONTIME interrupts during specific
sections of your BASIC program.
You must
execute the ONTIME statement again before the specific
interrupts enable.
Important: When the CLEARI
statement is LISTED it appears as
CLEAR
I.
5.4
Description of Statements
5.4.1
Statement: CALL [integer]
5.4.2
Statement: CLEAR
5.4.3
Statement: CLEARI
(clear interrupts)