User's Manual

XEROX DOCUPRINT 96/4635/180 NPS SYSTEM OVERVIEW GUIDE 2-1
2. 2Printer Controller
This chapter describes the DocuPrint Printer Controller. It includes a
list of component hardware, software and fonts, and discusses the
key elements of software operation.
Printer Controller overview
The Printer Controller manages print options, provides the user
interface, and runs system management and diagnostic operations
on demand. The Printer Controller receives PostScript, HP PCL 5e,
HP PCL 5c for highlight color models, and ASCII files from the client
through an Ethernet, FDDI, or Token Ring network.
The Printer Controller detects which protocol is being used for a print
data file that is being sent. Print data can be sent through TCP/IP,
AppleTalk, or Novell NetWare packets.
Once the print data file has been received:
• Print data is separated from print option parameters
• Print data is stored on the Printer Controller fixed disk
• Print options parameters are stored in the Job Pool Manager
(JPM) database.
The print data is stored on the fixed disk for queuing, for multiple copy
processing, or for recovering from system errors and printer faults.
The Job Pool Manager (JPM) maintains a database of all jobs. The
database contains a reference to the print data on the fixed disk, as
well as the print options parameters for the print data. Data in the
JPM database is scanned and sequenced for maximum efficiency.
The JPM responds to the Printer Controller commands that affect the
Job Pool, such as deleting, holding, or prioritizing jobs.
When the Printer Controller begins processing a job, it sends the
print data to the decomposer. The decomposer converts the print
data into a bitmap in the resolution appropriate to the printing device.
For a color job, one bitmap is created; the color spaces are
interleaved on a pixel basis.
The decomposer utilizes font data from font files stored on the Printer
Controller fixed disk or font information sent to the Printer Controller
with the print job.
When processed data comes back from the decomposer, the Printer
Controller Device Driver transmits the print data and print option
parameters to the printer and initiates printing.