Document Type and Number:
Japanese Patent JPS6155126
Kind Code:
B2
Abstract:
PURPOSE:To shorten the processing time, by setting FF at the time of rise of a signal, loading a detection address in the store register within a non-display period of time in the interruption generation circuit, generating an interruption signal to software, and carrying out the interruption with a simple constitution. CONSTITUTION:When a light pen 7 is applied to a character and so on which are displayed in the CRT monitor 6, and a light pen switch 7 is pushed, both the write- in pulse signal and the light pen switch signal, which show that light from the pen 7 has been detected, are sent to the light pen signal control circuit 11. FF22 is set at the time of rise of the light pen switch signal in the aforesaid circuit, and a detection address is loaded in the store register 8 within a non-display period of time in the interruption generation circuit 10 in order to generate an interruption signal to software. On the other hand, in case the pen 7 is pointed toward the light source other than a phosphor, FF22 is reset and the interruption signal is not generated, since the write-in pulse signal is generated even within a non-display period of time. Thus, it is possible to perform an interruption with a simple constitution and shorten the processing time.
Inventors:
YAMAMOTO TATSUO
Application Number:
JP4374379A
Publication Date:
November 26, 1986
Filing Date:
April 11, 1979
Export Citation:
Assignee:
TOKYO SHIBAURA ELECTRIC CO
International Classes:
G06F3/037; G06F3/153