HP 3000 Manuals HP 3000 Manuals
Appendix B SNA Character String (SCS) Support
SNA IMF supports SNA Character String (SCS) control codes, allowing
programs on the HP 3000 to emulate LU.T1 (SCS mode) printers. SNA IMF
also supports the 3270 data stream, so HP programs can also emulate LU.T3
(3270 mode) printers. Only one mode can be active at a time.
If your program is emulating an LU.T1 printer, it must be in transparent
mode. The data stream, with SCS codes, is passed untranslated into the
internal screen image. Your program is responsible for interpreting the
SCS codes.
The SCS data stream has fifty-six control codes. The IBM 3287 printer
supports 18 of the SCS control codes, and HP printers support 17 of those
18 control codes. The Set Attribute (SA)SCS control code is the only
code supported by the IBM 3287 that HP printers do not support. The SA
control code is an extension of the SCS data stream and is considered an
option by IBM. Also considered optional SCS extensions are the Structured
Field and Attribute Processing (SFAP)features. SNA IMF does not support
these options.
An LU.T1 session can support only a screen image of 3870 bytes and an RU
size of 3584 bytes. If you exceed this RU limit, the screen image will
be overwritten.
For a complete description of the 17 supported SCS codes, refer to the
IBM 3287 Printer Models 1 and 2 Component Description (IBM P/N
GA26-3153).
As with the IBM 3287 printer, you must physically alignpaper forms at the
first line to be printed when you insert forms into the printer. This
action will ensure correct feeding of the forms. Also, any change in
format (SHF, SLD, SVF) must be followed by the appropriate synchronizing
function (CR, NL, FF) in order to maintain format integrity.
Table B-1 lists the SCS codes supported by SNA IMF.
Table B-1. SCS Codes Supported by SNA IMF
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| SCS Code EBCDIC (hex) SCS Name |
| |
| CR 0D Carriage Return |
| |
| LF 25 Line Feed |
| |
| NL 15 New Line |
| |
| BS 16 Back Space |
| |
| FF 0C Form Feed |
| |
| HT 05 Horizontal Tab |
| |
| VT 0B Vertical Tab |
| |
| SHF 2BC1 Set HorizontalFormat |
| |
| SVF 2BC2 Set VerticalFormat |
| |
| SLD 2BC6 Set Line Density |
| |
| VCS 04 nn Vertical ChannelSelect |
| |
| TRN 35 Transparent |
| |
| IRS 1E InterchangeRecord Separator |
| |
| BEL 2F Bell |
| |
| INP 24 Inhibit Presentation |
| |
| ENP 14 Enable Presentation |
| |
| GE 08 nn Graphics Escape |
| |
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