Rockwell Automation 8520 9/Series CNC Lathe - Manual (Page 272)

Introduction to Programming
Chapter 10
10-4
(2) Leader Section
The information between the tape start and the program start is called the
tape leader section. The leader section is a tape indexing section. On
punched tape, the holes punched in the leader section can be configured to
show alphanumeric characters. The control ignores information within the
leader section and does not perform a parity check on this information.
Important: A program start code must not appear within the leader
section. If the program start code appears, the control starts reading
information and assumes that it is the part program. This causes parity
errors or “nonsense” codes to be read in by the control.
(3) Program Start Code
The first end-of-block code (EOB code) after the leader section indicates
the beginning of the part program. The EOB code is designated with:
line feed (LF) ---- ASCII format
carriage return (CR) ---- EIA format
Important: When performing an EOB search, the search is executed from
the beginning of the part program, NOT from the point of display.
(4) O-Word Program Name
The program name, if on the tape, must follow the program start code.
When outputting to tape the program name can be determined by:
Program Name: If:
Manually keying in the program name ----
Selected from the first block of the
program
No name has been manually keyed in and the first
block contains an O-word, : (for EAI format), or N-word
after the program start code.
Selected from the program directory No name has been manually keyed in and no name
exists in the first block of the program. For the program
name to be taken from the directory screen the program
must be stored on that directory with the letter O
followed by up to 5 numeric digits. In this case the
control generates an O-word block as the first block of
the program written to tape.
No name is used A program will be stored on tape with no program name
if none of the above naming conditions are met.
(5) Part Program Section
A part program is made of blocks of information. Individual blocks
contain words that the control can interpret. Individual words are made up
of an address with a numeric value. For details on words and addresses,
see the remaining sections of this chapter.