Spooler FASTP Network Print Processes Manual

Installation and Configuration Considerations for
FASTPX25
Spooler FASTP Network Print Processes Manual — 427528-007
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X25AM Subdevice Configuration Considerations
X25AM Subdevice Configuration Considerations
FASTPX25 communicates with the printer using an X25AM subdevice (SU). The
following is a review of the subdevice parameters that apply to driving printers using
FASTPX25. Consult the following manuals for details of how to configure these
subdevices:
•
SCF Reference Manual for X25AM (for D-series systems)
•
X25AM Configuration and Management Manual (for G-series systems)
PROTOCOL
specifies the protocol that the subdevice uses. This should be set to PTP or ITI.
FASTPX25 treats both types of subdevices in the same manner. For typical
installations using a PAD to handle remote printers, use ITI so that X25AM sends
an X.29 INVITATION TO CLEAR packet at the end of a job. ITI prevents data loss
which can happen with PTP connections when the X.25 CLEAR packet gets
processed ahead of data packets still in-flight. The exact choice is dictated by the
type of PAD in use as follows:
PTP
should be used if the PAD does not expect to receive X.3 PAD commands,
which might be the case if the PAD is implemented in software. When the PTP
value is used, a corresponding DEVTYPE value of (9,0) must be specified.
ITI
should be used if the PAD expects to receive X.3 PAD commands, which is
typically the case for hardware PADs. With ITI, the default X.3 PAD parameters
can be altered in the X25AM subdevice configuration. When the ITI value is
used, a corresponding DEVTYPE value of (6,0) must be specified.
RECSIZE
specifies the maximum I/O size used by FASTPX25. This value must be in the
range 1 through 4095.
The value depends upon the capability of your P
AD/ printer. Larger values usually
produce higher throughput. A suggested starting point is 132 bytes.
RECSIZE is distinct from the WIDTH setting in the Spooler DEV configuration.
WIDTH in conjunction with TRUNC determines the maximum length of text lines
that can be printed and what to do when text exceeds the WIDTH.
For printers that support blocked mode I/Os (such as, the Printronix 5512, 5515,
5516, 5518, 5573, 5574, and 5577 printers), the RECSIZE can be smaller or larger
than WIDTH. If RECSIZE is smaller than WIDTH, more than one I/O buffer is
required to send a line. Conversely, if RECSIZE is larger than WIDTH, more than
one text line can be sent at a time.