A device type in the SAP System is the category of printer to be addressed. When you define an output device, choose the name of the device type that was defined in the SAP System for your printer model, such as Post2 for a PostScript printer. The device type is the total of all properties of an output device that the SAP System requires to control the output device correctly, such as control commands for font selection, page size, character set selection, and so on.
In most cases, the SAP System already provides the appropriate device type for the printer type for the printer model that you want to use. For a current list of the supported device types, see SAP Note 8928 in the SAP Service Marketplace. The attachment for the note contains most device types and can be downloaded. For information about very specific device types, see the attachments of the relevant SAP Notes.Most printers can also be controlled using a generic format, that is, a device-independent format, such as PostScript. They can be switched to a mode that is compatible with one of the standard printers for which an SAP device type is available
The SAPWIN data stream is processed in the sapwin.dll component. The sapwin.dll component is also used by the new front-end printing, as described in SAP Note 821519. SAPWIN processing errors therefore affect both print methods. Patches for SAPSprint and the new front-end printing are available in SAP Notes 927074 and 841175 respectively.
How to Import Device Type (Printer Type) for Spool / Printing administration in SAP