Title:
NUMBER DUPLICATION DETECTOR FOR SEQUENCE CONTROLLER
Document Type and Number:
Japanese Patent JPH01116703
Kind Code:
A
Abstract:
PURPOSE:To prevent an input/output card from operating erroneously when plural selective signals are outputted by comparing the number of digitals outputted by a selective switching means and address data to indicate the number of an input/output module outputted by a programmable controller, and outputting the selective signal. CONSTITUTION:When a second selective signal is outputted from an n-th input/ output module 20, a transistor (TR) on the n-th input/output module 20 is serially connected to a resistor R1, a potential in an input terminal A becomes higher, and from a reference voltage of a comparator 15 and the two input/output modules 20, the duplication of the input/output module numbers can be detected. That is, when the potential at the comparative input terminal A becomes higher than the reference voltage, the signal is outputted from the comparator 15, a continuous output signal is generated from a latch circuit 16, added to an interrupting terminal INT of a central processor 12, and the central processor 12 stops the input/output action. Thus, the input/output module can be prevented operating erroneously.
Inventors:
NIWA KUNIYUKI
FUJIMURA SUKEYUKI
FUJIMURA SUKEYUKI
Application Number:
JP27455187A
Publication Date:
May 09, 1989
Filing Date:
October 29, 1987
Export Citation:
Assignee:
TOYODA MACHINE WORKS LTD
International Classes:
G05B9/02; G05B19/04; G05B19/048; G05B19/05; (IPC1-7): G05B9/02; G05B19/04
Attorney, Agent or Firm:
Yusaku Goto