A “Soft” Reform for μ-80 Line Printer

This paper presents a method which enables a μ-80 line printer to possess the abiliy of “soft-interruption” with the aid of a real-time clock.
The clock interrupt processing program tests the state of the printer intermittently, and decides whether the printer will be started again. As a result, CPU can work simultaneously with the printer. Thus CPU can be fully utilized and the utilization factor of the system is heightened accordingly.