Title:
TROUBLE DETECTOR OF TIMEESHARING COUNTER
Document Type and Number:
Japanese Patent JPS54144566
Kind Code:
A
Abstract:
PURPOSE:To detect the troubles of a time-sharing counter, by comparing the counting information of a specified address of a counting information memory storage for performing timer operation, etc. and the contents of a counter counting under the same condition as a counting condition of said counting information memory storage. CONSTITUTION:When a sequence controller SC begins to read a timer instruction, a counting arithmetic portion 5 of a time-sharing timer TDT discriminates as to whether or not a condition updating the counting contents of a timer is formed, and houses updating information to an address of interest of a counting information memory storage 4 when the condition is organized. When an address counter 2 of the sequence controller SC appoints a specified address, a counter control circuit CC judges a condition of timer updating apart from the counting arithmetic portion 5, and updates the contents of a counter CW. A coincidence decision circuit COM compares the contents of the counter CW and the contents of the memory storage 4, and generates output when both contents discord.
Inventors:
OSAKO KAZUYOSHI
Application Number:
JP5234178A
Publication Date:
November 10, 1979
Filing Date:
May 02, 1978
Export Citation:
Assignee:
HITACHI LTD
International Classes:
H03K21/40; G05B19/02; G05B23/02; (IPC1-7): G05B19/02; G05B23/02; H03K21/34