In many environments (including mainframes and most minicomputers), printable data
normally contains a carriage control character. The carriage control character acts
as a vertical tab command to position the paper at the start of a new page, at a specified
line on the page, or to control skipping to the next line. The characters can be one
of two types: ANSI carriage control or machine carriage control.
- ANSI carriage control characters
- The most universal carriage control is ANSI, which consists of a single character
that is a prefix for the print line. The standard ANSI characters are:
| ANSI |
Command |
| space |
Single space the line and print. |
| 0 |
Double space the line and print. |
| - |
Triple space the line and print. |
| + |
Do not space the line and print. |
| 1 |
Skip to channel 1 (the top of the form, by convention). |
| 2–9 |
Skip to hardware-defined position on the page. |
| A,B,C |
Defined by a vertical tab record or FCB. |
All ANSI control characters do the required spacing before the line is printed. ANSI
controls can be encoded in EBCDIC (CCTYPE=A) or in ASCII (CCTYPE=Z).
- Machine carriage control characters
- Machine carriage controls were originally the actual hardware control commands for
IBM printers and are often used on non-IBM systems. Machine controls are literal values,
not symbols. They are not represented as characters in any encoding and, therefore,
machine controls cannot be translated. Typical machine controls are:
| Machine |
Command |
| X'09' |
Print the line and single space. |
| X'11' |
Print the line and double space. |
| X'19' |
Print the line and triple space. |
| X'01' |
Print the line and do not space. |
| X'0B' |
Space one line immediately (do not print). |
| X'89' |
Print the line and then skip to channel 1 (top of form, by convention). |
| X'8B' |
Skip to channel 1 immediately (do not print). |
Machine controls print before they do any required spacing. There are many more machine
control commands than ANSI. Carriage controls can be present in a print file or not,
but every record in the file must contain a carriage control if the controls are to
be used. If the file contains carriage controls, but CC=NO is specified to ACIF, the
carriage controls are treated as printing characters. If no carriage controls are
specified, the file is printed as though it is single spaced.