Input Subsystem; Control Subsystem - Xerox 4050 Product Reference

HARDWARE COMPONENTS

Input subsystem

Control subsystem

The control subsystem
performs . . .
All data handling
•
Formatting
•
Buffering
•
Operational control
•
2-12
The input subsystem receives print and nonprint file input
through the offline interface, the OEM interface, the DEC
interface, the Ethernet interface, or the online interface.
A selectable system allows a choice between operational modes.
Input is obtained from the sources shown in table 2-2.
Table 2-2.
Interface Source
Offline 9-track (1600 or 6250 bpi) magnetic tape using the magnetic
tape drive or from 18-track cartridge using the 180 18-track
CTS.
Ethernet Workstations (such as the 6085) and graphic scanners (150 GIS
or 7650 Pro Imager) in a shared or unshared, but accessible,
network.
OEM A remote IBM-compatible host computer system using the 871-
Communications Module (CM). This permits ASCII and EBCDIC
data transmission to the 4050/4090/4450/4650 LPS.
Transmissions can occur in the System Network Architecture
and Synchronous Data Link Control (SNA and SDLC) protocol
environment and the Binary Synchronous Communications
(BSC) protocol environment.
DEC A VAX/VMS system. This permits synchronous data transmission
to the 4050/4090/4450/4650 LPS in a DEC Data Communications
Message Protocol (DDCMP) environment.
Online A channel-attached host. All IBM systems which support the
channel-attached 3811/3211 and 4245 interface are supported.
(Non-IBM systems are supported through a variety of third-party
connections.)
Table 2-3 is a summary of the control subsystem.
Table 2-3.
It consists of . . .
System controller
•
Main memory
•
Terminal
•
Two to four system disks
•
Interface and control electronics
•
The interface and control electronics handle controller-to-device
communications and control of specific device functions. They
provide the necessary interfacing between the input/output (I/O)
Interface sources
Control subsystem features
The system controller main
memory directs . . .
Page formatting
•
System control
•
FSL/JSL compilation
•
System diagnostics
•
XEROX 4050/4090/4450/4650 LPS PRODUCT REFERENCE