The following PostScript command allows you to switch from PostScript to HP PCL emulation on the serial port of the LaserWriter Pro 810. This code can be downloaded from any of the ports that currently have PostScript set as the language. If only the serial port is being used, then once the language of the serial port has been changed to HP PCL, you cannot return back to PostScript except by using the control panelon the printer, or by downloading the PostScript code using another port such as Ethernet, or LocalTalk.
PostScript Code
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Caution:
If you choose to use the PostScript code provided in this article, you assume all risks involved in making these changes. PostScript code, if not entered correctly, can place the LaserWriter into a condition requiring service.
To select either PCL or PostScript printer job language, before sending your print job to the printer, transmit the following "emulator" command:
(%Serial%)<</Interpreter PARAMETER /Protocol TYPE>>setdevparams
Valid PARAMETER values are /PostScript and /LaserJetIIP
Valid TYPE values are /Normal when PARAMETER is /PostScript, and /Raw when PARAMETER is LaserJetIIP.
Example:
(%Serial%)<</Interpreter /LaserJetIIP /Protocol /Raw>>setdevparams
This emulator command string places the RS232 Input Port's Printer Type in LaserJetIIP emulation.
Language switching
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If you would like "on-the-fly" functionality of being able to switch languages at any time on the serial port, you need to set the serial port for PostScript, and then download/include the following PostScript code at the front of the PCL job to switch temporarily to HP PCL emulation:
statusdict begin 5 setsoftwareiomode end
Upon completion of the job, the serial port's page description language will switch back to PostScript though the last line of the PCL job must have the following command string:
ESC DEL 0 (which is hex '1B 7F 30')
NOTE:
This command string contains spaces for readability--don't include spaces when entering this command in your file. For example, without spaces it reads: 'ESCDEL0' or '1B7F30'. Also, you must follow this string with a Control-D.
This PCL control string returns the printer back into the PostScript mode when the current HP PCL job is completed.