Rockwell Automation 1746-BAS BASIC LANGUAGE - Manual (Page 140)

Publication 1746-RM001A-US-P
11-10 Status Functions
CALL 95 – Get Number of
Characters in PRT1
Buffers Purpose
Use CALL 95 to retrieve the number of characters in the chosen buffer of port
PRT1.
You must PUSH which buffer you want examined:
•
PUSH 1 for the input buffer
•
PUSH 0 for the output buffer
One POP is required to get the number of characters.
Syntax
PUSH [buffer selection]
CALL 95
POP [number of characters]
Example
>1 REM EXAMPLE PROGRAM
>10 PUSH 0 : REM EXAMINES THE OUTPUT BUFFER
>20 CALL 95
>30 POP X : REM GET THE NUMBER OF CHARACTERS
>40 PRINT “NUMBER OF CHARACTERS IN PRT1 OUTPUT BUFFER IS ”,X
>50 END
READY
>RUN
NUMBER OF CHARACTERS IN PRT1 OUTPUT BUFFER IS 0
READY
>