ASCII or TBCP

[IT News]

The data format default setting for some PS drivers is ASCII and for some
other ones is TBCP.
What are the advantages of using one over the other, please?

Thanks!

[Helge Blischke]

IT News wrote:

TBCP is a protocol that manages transferring binary (8 bit wide) data over a
7 bit wide transport channel (e.g. a serial port).

Note that there still are printers around the PS interpreter of which
behaves like hooked to a 7 bit wide serial port even if connected to
a network channel.

Helge

[IT News]

"Helge Blischke" <h.bli...@acm.org> wrote in message
news:72npkaF...@mid.individual.net...

Thanks Helge.
What I do not understand is that I have noticed that the PS default is
simply manufacture related, however, some (brand new) printers (from the
same manufacture) default to TBCP and some other (brand new) printers (from
the same manufacture) default to ASCII.
So far I have gathered the following info (including yours:)

ASCII Protocol

According to Adobe's "Serial and Parallel Communications Protocols
Specification," The "standard protocol" typically consists of data encoded
as ASCII text values, plus some control codes. These control characters are
handled at the printer. Communication channels like serial, parallel and
Ethernet are considered to support standard protocol. With ASCII, the same
data would have to be converted to ASCII, meaning that each binary byte
turns in to two ASCII bytes. This was A Very Big Deal when we hooked up
printers using serial cables, less so with parallel connections and with
USB/network connections; it's not all that material any longer, unless
you're printing a LOT of images using binary EPS or the like.

Reading ASCII files (Advanced) - see page 40 in the following document:

http://www.fho-emden.de/~hoffmann/pstutor22112002.pdf

Binary Protocol

Binary Communications Protocol (BCP) consists of data encoded as values in
the range 0-255. The primary advantage of BCP is data compression (reduced
file size). Communication channels like AppleTalk are considered to support
binary protocol. The communications channel must be connected to a device
that is capable of decoding the Binary protocol.

Tagged Binary Protocol

There still are printers around, the PS interpreter of which behaves like

hooked to a 7 bit wide serial port even if connected to a network channel.

Tagged Binary Core Protocol (TBCP) is a protocol that allows binary encoded
PostScript print jobs to be sent to a device over a non-binary protocol
communication channel. It manages transferring binary (8 bit wide) data over
a 7 bit wide transport channel (e.g. a serial port). TBCP is also one method
of sending binary data *as* binary data without risking problems that would
ordinarily result from random occurrences of characters like Ctrl+D.

TBCP can be use to transform a communication channel that supports standard
protocol (ASCII) into a communication channel that can transfer Binary
encoded data.

Typical errors encountered when sending Binary encoded data to a printer
that is expecting ASCII data from a TCP/IP or USB connection are:

a.. A partial page of garbage characters.
b.. Blank pages or pages with one line of gibberish.
c.. Blank pages are printed until the printer runs out of paper.
d.. Multiple PostScript errors.
e.. Smeared output.
f.. Jobs "stuck" in DeskTop Printer.
g.. Computer "freezes" when trying to print.
I would appreciate any additional info or elaboration :)

Thanks!