Xerox ALLY PLUSTM 6287 - Manual (Page 61)

Page 3-21 CONFIGURATION
Transparency Modes (Group #60)
Most ASCII and EBCDIC printers have features that are not available on
IBM printers. If the user’s host application is aware that the destination of
the data may be a non-IBM printer attached to a protocol converter, the
application can take advantage of the printer’s advanced features. To
activate a particular printer feature, the application will send a transparent
command in the data stream. (Refer to the printer user’s manual for a list of
available printer commands.)
A transparent printer command, or transparency, consists of a trigger
(character code) followed by the sequence that will activate a particular
printer feature. The trigger alerts the protocol converter that the data that
follows it is a printer command that should be sent directly to the printer
without translation. If the appropriate form of transparency is activated in
this option group, the ALLY PLUS will recognize the trigger and respond
appropriately to that form of transparency. The ALLY PLUS can use
standard IBM 35h and Xerox 36h transparency, and the ALLY PLUS also
provides its own versions of transparency.
Note: If the user or the user’s application embeds transparent or pseudo
transparent strings in the data stream, Option #12 — SCS right margin and
Option #22 — DSC right margin should be set to 00 (infinite line length),
Option #14 — SCS bottom margin and Option #24 — DSC bottom margin
should be set to 00 (infinite page length), and Option #70 — DisplayWrite
370 support should be set to 00 (disabled). Otherwise, unpredictable
formatting errors could occur.
60 — Allow IBM 35h transparency
This form of transparency is valid only in SCS data streams. In IBM 35h
transparency, the trigger character is 35h, and it indicates the start of the
transparent data stream. The 35h is followed by a count byte that indicates
the length, in bytes, of the transparent data stream, not counting the count
byte itself. The count byte is followed by the actual data to be sent. For
instance, the following code will send a Xerox 4045 printer reset command
(s+X CR/LF) using 35h transparency:
35051B2B580D0A
This includes the trigger (35), the count byte (05), and the three bytes for
s+X CR/LF (1B, 2B, 58, 0D, 0A).
The user can generate any possible 8-bit command or data byte that is to be
sent to the printer. There is a one-to-one correspondence between what is
received by the ALLY PLUS and what is sent to the printer.