TN3270E Printer Link Driver

DMTTPT is the primary module for the TN3270E printer link driver task. DMTPCR formats individual records into 3270 data stream format on behalf of DMTTPT. TN3270E-type links send output spool files to printers attached in a TCP/IP network with the capability to initiate a TN3270E session, such as emulators, capable of supporting 3270 print streams. TN3270E-type links also support Graphic Data Display Manager (GDDM) files that are sent to 3270-type printers.

DMTTPT is very similar in processing to DMTRPT, except the printer is attached within a TCP/IP network rather than channel attached to the host. The main differences in processing are:
  • The session must be initiated from the printer side rather than by RSCS. A TN3270E session must first be established to the VM TCP/IP stack. Once the session is successfully established, VM TCP/IP will create a printer logical device and attach it to RSCS. Once attached to RSCS, the TN3270E-type printer link can be started. There are configuration steps that need to be performed in the VM TCP/IP stack; see z/VM: RSCS Networking Planning and Configuration and z/VM: TCP/IP Planning and Customization for details on configuration steps.
  • During intialization, DMTTPT will ensure the printer is attached via TN3270E; otherwise the link will terminate.
DMTTPT performs the following functions between VM and the printer:
  • Sends spool files to the remote printer
  • Sends messages and responses to the remote printer
  • Reads asynchronous Intelligent Printer Data Stream (IPDS) interrupts from the printer.