Data communication equipment for transferring data
First Claim
1. Data communication equipment for transferring data comprising:
- three central processing units each having a communication path serially connected to others of said three central processing units to form a unidirectional serial communication loop between said three central processing units for transferring data, said data including a designation of a specific one of said three central processing units by which said data is to be processed, a first central processing unit of said three central processing units including a bidirectional communication path;
a memory provided for each of said three central processing units to store data transferred thereto;
a monitor device, connected to said bidirectional communication path of only said first central processing unit, for displaying diagnostic data indicating a trouble condition of any of a plurality of sensors connected to said three central processing units;
an output device provided in said monitor device for outputting request data to said first central processing unit to request data from said memory of said first central processing unit; and
a mutual communication circuit, connected to said first central processing unit and said output device of said monitor device, for allowing bidirectional data communication between said monitor device and said first central processing unit, for temporarily storing said request data from said monitor device and said data requested from said memory of said first central processing unit, for outputting said temporarily stored data requested from said monitor device to said first central processing unit when said first central processing unit is ready to receive said data requested, and for outputting said temporarily stored data requested to said monitor device when said monitor device is ready to receive said data requested;
each respective one of said three central processing units processing data transferred thereto over said unidirectional serial communication loop if said data includes a designation code designating the respective one of said three central processing units, and each respective one of said three central processing units transferring without processing data to a next one of said three central processing units connected to said serial communication path, if said designation code designates another respective one of said three central processing units; and
wherein each respective one of said three central processing units transfer response data indicating a trouble condition of respective ones of said plurality of sensors over said communication loop to said monitor device via said first central processing unit for display.
0 Assignments
0 Petitions
Accused Products
Abstract
Data communication equipment which includes a plurality of CPUs and transfers data between these CPUs, and which simplifies the circuit construction necessary for the data transfer. A monitor device transfers a request data containing a CPU number (corresponding to CPUN 1) storing a desired trouble data and an address (corresponding to ADR 1) storing the trouble data, to a second CPU. The requested data is sequentially transferred to the first CPU and the third CPU, and the CPU designated by CPUN 1 transfers the trouble data (DATAO 1, DATAO 3) and the address (ADRO 1, ADRO 3) storing the trouble data, to the monitor device. For this reason, each CPU need not be connected individually to the monitor device 43.
41 Citations
8 Claims
-
1. Data communication equipment for transferring data comprising:
-
three central processing units each having a communication path serially connected to others of said three central processing units to form a unidirectional serial communication loop between said three central processing units for transferring data, said data including a designation of a specific one of said three central processing units by which said data is to be processed, a first central processing unit of said three central processing units including a bidirectional communication path; a memory provided for each of said three central processing units to store data transferred thereto; a monitor device, connected to said bidirectional communication path of only said first central processing unit, for displaying diagnostic data indicating a trouble condition of any of a plurality of sensors connected to said three central processing units; an output device provided in said monitor device for outputting request data to said first central processing unit to request data from said memory of said first central processing unit; and a mutual communication circuit, connected to said first central processing unit and said output device of said monitor device, for allowing bidirectional data communication between said monitor device and said first central processing unit, for temporarily storing said request data from said monitor device and said data requested from said memory of said first central processing unit, for outputting said temporarily stored data requested from said monitor device to said first central processing unit when said first central processing unit is ready to receive said data requested, and for outputting said temporarily stored data requested to said monitor device when said monitor device is ready to receive said data requested; each respective one of said three central processing units processing data transferred thereto over said unidirectional serial communication loop if said data includes a designation code designating the respective one of said three central processing units, and each respective one of said three central processing units transferring without processing data to a next one of said three central processing units connected to said serial communication path, if said designation code designates another respective one of said three central processing units; and wherein each respective one of said three central processing units transfer response data indicating a trouble condition of respective ones of said plurality of sensors over said communication loop to said monitor device via said first central processing unit for display. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
Specification