Printer Control Interface Between Host Data Processor and Word Processing System Printer
Original Publication Date: 1984-Feb-01
Included in the Prior Art Database: 2005-Feb-02
In the present-day information processing environment, the host data processor may provide its printed output on a word processing system printer which is emulating a data processing system printer, such as the IBM 3287. In such an emulation the connection is via a high speed asynchronous half duplex coaxial link between the printer being emulated and the controller or multiplex unit for the host data processor. The protocol used on the link requires a large number of simple data transactions which require immediate response. The word processor emulation responds to these transactions without the intervention of the microprocessor associated with the word processing system. This is accomplished by a parallel data routing method in the control module which will be described hereinafter.