IBM 3800 Printing Subsystem
The IBM 3800 Printing Subsystem is a high-speed, nonimpact printer that com­
bines electro-photographic and laser technology. The 3800 printer can achieve
speeds of up to 20,040 lines/minute, while several unique features give the user the
ability to control the characteristics of printed output.
The features of the 3800 printer include:
Forms control buffer -controls the amount of vertical space between printed
lines. The user can specify vertical spacing of 6, 8, or 12 lines/inch.
Multiple copy printing -allows the user to request multiple copies without the
use of carbon paper. The 3800 uses its high speed to repeat-print the specified
number of originals.
Copy modification -allows the user to print or suppress predefined information
on specified copies of a page. For example, a different name and address can
be printed on each copy of a page.
Forms overlay -allows the user to specify a form or grid to be printed (flashed)
from a negative while output is being printed inside the form.
Character arrangement tables -allow the user to specify which predefined
character set to use for printing a data set. Each character set contains up to
64 printable characters.
Character modification -allows character sets to be modified or extended to
meet the user's needs.
For detailed information on the 3800 Printing Subsystem see:
Introducing the IBM 3800 Printing Subsystem and Its Programming
Concepts of the IBM 3800 Printing Subsystem IBM 3800 Printing Subsystem Programmer's Guide, OS/VSl, OS/VS2 Reference Manual for the IBM 3800 Printing Subsystem. VM/SP supports the 3800 printer as a dedicated device, as a real sp00ling device,
and as a virtual spooling device.
Using the 3800 Printer as a Dedicated Device VM/SP allows a virtual machine that is configured to support a real 3800 to attach
the 3800 for that machine's exclusive use. When used as a dedicated device, VM/SP supports all of the facilities of the 3800. Using the 3800 Printer as a Real Spooling Device VM/SP allows users of spool files to print their files on an IBM 3800 Printing Sub­ system. The copy modification, forms overlay, character modification, and multiple
copy features are fully supported. However, when the 3800 is used as a real spool-
IBM 3800 Printing Subsystem 295

Specifying Printer Options Control Tables
ing device, only one character arrangement table may be specified for each spool
file. In addition, the entire spool file must be printed with the same line spacing on
each page.
Parameters on five commands enable the user to take advantage of the 3800 print­
er's capabilities. The CHANGE, SPOOL, and START commands allow the user to
specify the character arrangement table, copy modifications, forms overlay, and
FCB to be used for printing. The BACKSPAC and QUERY commands also sup­
port the 3800 printer.
Three utilities, GENIMAGE, IMAGELIB, and IMAGEMOD, construct and modi­
fy the character arrangement tables, graphic modifications, copy modifications, and
FCBs used by the 3800. DIAGNOSE Code X'74' is invoked by IMAGELIB and IMAGEMOD to load and save this control information as a named system.
Finally, the NAME3800 macro instruction allows the user to create the named sys­
tem that contains the control information needed to print a spool file.
Five parameters on the SPOOL and CHANGE commands support the 3800 printer
as a real spooling device. (See the CP Command Reference for General Users for
detailed coding information.)
FLASH -identifies the form overlay, if any, to be used when printing the file
CHARS -names the character arrangement table to be used to print the file MODIFY - indicates the copy modification module, if any, to be used when
printing the file • FCB -specifies the name of the forms control buffer to be used for the file COpy - indicates the number of copies to be printed.
The START command includes parameters that enable the VM/SP operator to
name the character arrangement table and the FCB to be used for the separator
page. The operator can also identify, via the FLASH operand of the START
command, the forms overlay currently loaded in the 3800. In addition, the opera­
tor uses the IMAGE parameter to specify the named system to be used to print the
spool file. Finally, by specifying the PURGE parameter, the operator can purge all
spool files that cause errors when loaded into the 3800. See the VM/SP Operator's Guide for further information on the START command. VM/SP uses the OS/VS utility IEBIMAGE to create and dynamically modify
character arrangement tables, copy modifications, graphic modifications, and
FCBs. Three service programs, GENIMAGE, IMAGELIB, and IMAGEMOD, interface with IEBIMAGE.
GENIMAGE creates or modifies text files on a CMS disk. These text files contain
the images to be used by the 3800 Printing Subsystem.
296 VM/SP System Programmer's Guide