Erasing typewriter with automatic/manual selection

In an erasing typewriter including

• key actuated means for generating signals representing an actuated key,
• memory means for storing an ordered sequence of signals representing a sequence of operator actuated keys,
• print means including print and erase media for executing a print cycle to at times print a character at a print point if said print medium is enabled, or to erase a character at a print point if said erase medium is enabled,
• print point position control means responsive to said key actuated means for displacing said print means and for accessing a selected location of said memory means corresponding to said print point, and
• erase means operative in response to actuation of an erase key for initiating a sequence of operations including:
• (a) actuating said print point position control means to displace said print point one character space toward a left margin,
• (b) accessing said memory means at a selected location corresponding to said displaced print point for reading signals stored at said selected location,
• (c) actuating said print means and enabling said
• erase medium to execute a print cycle to erase a character at said print point corresponding to signals read from said memory means,
• the improvement comprising:
• first means responsive to absence of signals representing an erasable character at said selected location of said memory means to inhibit said print cycle and to enable said erase medium and said print means to execute a print cycle on a following key actuation only if said following key actuation corresponds to actuation of a key representing an erasable character.