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Communication protocols, Simple communication protocol, Communication protocols 3 – Apple LaserWriter Select 310 Printer User Manual

Page 61: Simple communication protocol 3

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C H A P T E R 3

Communication Channels

Communication Protocols

49

Figure 3-1

SCC operator encoding

Communication Protocols

3

The LaserWriter Select 310 printer supports both simple and binary communication
protocols for serial and parallel channels. Several character codes in both protocols are
reserved for communication functions and are not passed through the PostScript
interpreter. The default protocol is binary. The section “Setting Device Parameters,”
“setsoftwareiomode,” in Chapter 2, describes how to change the default protocol
from binary to simple.

Simple Communication Protocol

3

Table 3-4 lists the character codes reserved for communication functions in the simple
communication protocol. The ASCII character codes are given in decimal.

Table 3-4

Reserved characters in simple communication protocol

Character

ASCII
code

Function

Control-C

3

Interrupt. Causes execution of the PostScript language
interrupt

error. See the PostScript Language Reference

Manual, Chapter 6, for further information on interrupt.

Control-D

4

End of file.

Control-S

19

Stop output (XOFF). Functional only if XON/XOFF flow
control is in use.

continued

Example

9 19200 2 setsccbatch

sum of decimal values :

Feature Description

Decimal

value

Parity

Even

2

Flow control

XON/XOFF

0

Data bits

Standard

0

Stop bits

1

0

baud rate: 19200

channel type: 8-pin serial