PS Protocol

Option

To differentiate data from the special control characters, any data that is the same as one of the following special control characters must be quoted.

ASCII

ASCII

ASCII Hex

Control Function

Keyboard

Name

 

 

 

 

 

 

^A

SOH

0x01

Quote data character

^C

ETX

0x03

Abort job and flush to end of file

^D

EOT

0x04

End-of-file marker

^E

ENQ

0x05

(Reserved for future use)

^Q

DC1

0x11

XON in XON/XOFF flow control

^S

DC3

0x13

XOFF in XON/XOFF flow control

T

DC4

0x14

Job status request

^\

FS

0x1C

(Reserved for future use)

 

 

 

 

A data byte is quoted by replacing it with a two-character sequence. The first character is a ^A (ASCII hex 0x01), and the second character is the character itself XORed with the ASCII value 0x40. For example, to send the value 0x14(^T) as data, send the two-character sequence 0x01 0x54 (^a T) instead. (ASCII “T” is the result of XORing ^T with 0x40).

This method of quoting guarantees that whenever the printer receives any of the eight control characters, the control function is intended regardless of whether the preceding character is a ^A. Any data byte not equal to one of the eight special control characters is transmitted by sending the data byte.

For more information on BCP and quoting, see the PostScript Language Reference Manual (Adobe Systems, Inc., Reading, MA: Addi- son-Wesley, 1990, ISBN 0-201-18127-4), the “Adobe Serial and Parallel Communications Protocols Specification” (in Adobe Developer Support. Adobe Systems, Inc., February 14, 1992), and the “PostScript Language Reference Manual” (in Supplement for Version 2011, Adobe Systems, Inc., January 24, 1992).

Additional Technical Information

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