Carnation Software
MacWise - Macintosh Terminal Emulation - telnet / serial for OS X - Wyse, Viewpoint, VT100, VT220

Printing directly to a printer using PCL commands with MacWise
(version 12.14 or later)

Printer Command Language, more commonly referred to as PCL, is a page description language developed by HP as a printer protocol and has become a de facto industry standard for most printer manufacturers. It was originally developed for early inkjet printers in 1984.

MacWise supports slave (aux) printing. When the host sends a Printer On command, MacWise records all data to a print buffer until the host sends a Printer Off command.

When the option to "Pass Control Characters to Printer (Direct PCL Printing)" is enabled in Printer Setup, MacWise will print directly to the Mac default printer using printer commands supplied by the host.

The standard Mac print dialog box is bypassed when in this mode.


When PCL commands are included in the print job sent from the host to MacWise, the host can control printer features such as bold text, lines per inch, margins and much more.

Many host computers have already been programmed to send PCL commands when slave printing.

In that case, no additional host programming should be required.

Here is a table showing some of the more common PCL commands.

For more information about PCL, here is the PCL Technical Reference Manual.

NOTE: Printing in this mode is limited to 256 characters per line.

To enable this feature in MacWise...

Select Printer Setup from the File Menu in MacWise.

Then put a check mark on "Pass Control Characters to Printer (Direct PCL Printing)"

Pasted Graphic.pict

Since MacWise prints directly to the default Mac printer, you will need to look at your Printer preferences to select your default printer.

To set your Mac default printer...

1. Select System Preferences from the Apple Menu in the upper left corner of your screen.

2. Click on Print & Fax

3. Chose your default printer



This is an example of a basic program on the host that will turn slave printing on, send PCL commands and text to MacWise, then turn slave printing off.

This simple example just prints the first line in bold and the second line in plain text.

Note that the Printer On and Off commands in this sample are FOR VT100. See the table at the bottom of this document for other terminal codes.


001 * Test bold and plain text with direct PCL printing
002 * PCL codes are sent directly to the default printer.
003 * Bypassing the Mac print dialog box.
004 *

005 esc = CHAR(27)

006 PRINT esc:"[5i":;  *Printer On
007 PRINT esc:"%-12345X@PJL SET RESOLUTION=300"; *Initialize PCL printing
008 PRINT esc:"(s3B"; *Turn on Bold
009 PRINT "This is the title of this document in bold"
010 PRINT esc:"(s0B"; *Turn off bold
012 PRINT "This is some plain text":
013 PRINT esc:"E"; *Exit PCL printing
014 PRINT esc:"%-12345X":; *End PCL printing
015 PRINT esc:"[4i":;  *Printer Off
016 END

Terminal emulation codes for turning the printer on and off.

These are the standard codes that MacWise will respond to.
Note that when MacWise is in the Direct PCL printing mode, it uses transparent printing
(text goes directly to the printer and not to the screen). But it will respond to all codes in this table.

  Printer On Printer Off Transparent Print On Transparent Print Off
Wyse 50 Ctrl R Ctrl T Ctrl X Ctrl T
Wyse 60 / 370 Ctrl R or Esc d% Ctrl T Ctrl X or Esc d# Ctrl T or Esc d$
Viewpoint Ctrl R Ctrl T Esc 3 Esc 4
VT100 Esc [5i or Esc [?5i Esc [4i or Esc [?4i    
Prism Esc R Esc T    

Rich Love

Carnation Software