Intelligent Printer Data Stream (IPDS)
The Intelligent Printer Data Stream (IPDS) is a structured field data stream
designed to manage and control printer processes. (See Figure 2-5.)
It is easily
distinguished from previous
printer
data streams in that
it
supports all points
addressability (APA). The APA printing concept
allows
users to position text,
images,
vector
graphics, bar codes, and previously stored overlays at any point on
a page.
D D
. Intelligent
1--------1
Pri
nter
Data Stream
Host 3174 APA
Printer
Figure 2-5.
Intelligent
Printer Data Stream
Functional Description
System Attachment
The IPDS is transmitted from an application program to the
printer
within
structured fields that have been specifically designed for that purpose. The
IPDS
commands within the data stream enable the host to control:
• Media handling
• Downloading and managing of symbol sets (fonts) and
printer
..
stored objects,
such as overlays and page segments.
The
printer
can
later
use the stored objects to construct a printed page. The IPDS
can significantly reduce the load on the host processor and the number of
characters transmitted to the printer in many advanced printing applications.
The
IPDS is supported by:
• IBM 3174 Establishment Controller Configuration Support-A
(Release 2
or
higher)
• IBM 3174 Establishment Controller Configuration Support-S
(Release 4
or
higher)
• IBM 3174 Establishment Controller Configuration Support-B
(Release 1).
Printers capable of
IPDS
will
be supported by both SNA and non-SNA controllers.
Attachment protocols are as
follows:
• SNA
- Channel-attached
- SDLC-attached.
Note: Under SNA, support is limited to
LU
1 only.
• Non-SNA
- Channel-attached
- BSC-attached.
Note: Under non-SNA, IPDS is carried
only
in the
3270
data stream.
Chapter
2.
Features and Functions of the 3174
Controller
2-15