Ta Triumph-adler Aktiengesellschaft

Rudolf Spotka

Norbert Hofmann

Klaus Hagen

In a typewriter having a microprocessor for processing stored data according to a stored program, a method for detecting that a machine cover has been opened for servicing and for interrupting a data processing cycle in progress for as long as the cover remains open, said method including, in response to said interruption, the steps of storing in a portion of memory all data, addresses and flags required for the later continuation of the control cycle so that the programmable control unit can subsequently be brought into a condition in which it is insensitive to a great extent to the consequences of electrostatic discharges as may occur during servicing, and after closure of said machine cover after servicing, reconstructing the status of the control cycle prior to the termination, by entering the data, addresses and flags stored in memory into appropriate working registers and buffers.

Method and circuit arrangement for protection of typewriters or similar

A ribbon cassette with a memory makes it possible to provide a relatively exact determination of either the amount of ribbon remaining or the end of the ribbon with small mechanical outlay in an electronically controlled office machine or typewriter. A memory which contains external contacts and is capable of counting and storing values is provided from which base units can be subtracted by the control unit of the machine depending on the amount of ribbon advanced. The novel ribbon cassette makes it possible to dependably determine and display either the amount of ribbon remaining or the end of the ribbon.

Growing community of inventors

Nuremberg, Germany

Rudolf Spotka