Control method for distributed type remote I/O control...

Details Control method for distributed type remote I/O control... Control method for distributed type remote I/O control...

1998-07-16

2001-01-30

Lee, Thomas C. (Department: 2782)

Electrical computers and digital data processing systems: input/

Input/output data processing

Peripheral configuration

C709S208000, C709S238000, C710S014000, C710S015000

Reexamination Certificate

active

06182163

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates to a control method for a distributed type remote I/O unit control system and a data communication method, and more particularly to a control method for a distributed type remote I/O control system with a numerical control unit, a programmable controller unit, and other various types of control unit, in which a basic system of a control unit is connected to a plurality of distributed type remote I/O units through a serial communication system, and 1 vs. N communication is executed between the basic system of the control unit and each distributed type remote I/O unit.
BACKGROUND OF THE INVENTION
In the field of control system with a numerical control (NC) unit, a programmable controller (PC), or other various types of control unit, a distributed type remote I/O unit control system, in which a plurality of distributed type remote I/O units each for sending and receiving data to and from a basic system of the control unit are provided separately and bidirectional data communication is executed between the basic system of the control unit and the distributed type remote I/O units through a serial communication system, has been well known.
FIG. 31
shows a case where the conventional type of distributed type remote I/O control system is applied in an NC unit. In this figure, the distributed type remote I/O numerical control system has a basic system of the NC unit
1
, and a plurality of distributed type remote I/O units
2
each provided separately from the basic system of the NC unit
1
, and the basic system of the NC unit
1
and each of the distributed type remote I/O units
2
are connected to each other with two transmission signal lines
121
,
122
in the form of serial communication system, and bidirectional data communications is executed between the basic system of the NC unit
1
and each distributed type remote I/O unit
2
.
Of the transmission signal lines
121
and
122
which are in parallel to each other, the transmission signal line
121
is used for data transmission from the basic system of the NC unit
1
to the distributed type remote I/O unit
2
, while the other transmission signal line
122
is used for data transmission from the distributed type remote I/O unit
2
to the basic system of the NC unit
1
. It should be noted that a terminal module
4
is connected to the final distributed type remote I/O unit
2
.
The basic system of the NC unit
1
comprises an MPU
101
, a communication control section
102
having a transmission driver IC and a receiving driver IC, and a memory
103
for storing therein a control program, data, and the like, and a display unit
3
such as a CRT is connected thereto.
Each of the distributed type remote I/O units
2
comprises an MPU
111
, a communication control section
112
having a transmission driver IC and a receiving driver IC, a memory
113
with a control program or the like stored therein, a switch
114
for determining an operating state of each distributed type remote I/O unit
2
discretely, an output I/F section
115
for a mechanical device (equipment to be controlled) not shown herein, and an input I/F section
116
.
In the conventional type of distributed type remote I/O numerical control system as described above, the basic system of the NC unit
1
and the distributed type remote I/O units
2
are connected to each other in the form of serial communication system, and the distributed type remote I/O unit
2
is put under software control by the MPU
111
like the basic system of the NC unit
1
, and different communication lines are provided for transmission and receiving for the basic system of the NC unit
1
and the distributed type remote I/O unit
2
respectively.
FIG. 32
shows another example of the conventional technology in which the distributed type remote I/O control system is applied to an NC unit. In this distributed type remote I/O numerical control system, the basic system of the NC unit
1
and the distributed type remote I/O unit
2
are connected with one signal line
123
in the form of serial communication system, and bidirectional data communication between the basic system of the NC unit
1
and each distributed type remote I/O unit
2
is executed through the one signal line
123
.
This distributed type remote I/O numerical control system has substantially the same configuration as that of the distributed type remote I/O numerical control unit shown in
FIG. 31
excluding the point that the signal line
123
is used for both data transmission from the basic system of the NC unit
1
to the distributed type remote I/O unit
2
and data transmission from the distributed type remote I/O unit
2
to the basic system of the NC control unit
1
.
Description is made hereinafter for a software processing flow by the MPU
101
in the basic system of the NC unit
1
in the distributed type remote I/O numerical control system as described above with reference to FIG.
33
. When operation of the system is started up, as the MPU
101
in the basic system of the NC unit
1
has not checked what type of distributed type remote I/O unit
2
is connected to the basic system of the NC unit
1
, at first the MPU
101
generates a transmission frame for status request to each distributed type remote I/O unit
2
(step S
1
), and sends the status request frame to each distributed type remote I/O unit
2
(step S
2
).
As a response indicating reception of a status request frame by each distributed type remote I/O unit
2
, the distributed type remote I/O unit
2
sends a frame (status data frame) including status data (step S
3
), and the basic system of the NC unit
1
receiving the frame stores the received status data therein. Then, a status request is repeated successively to other distributed type remote I/O units
2
, and when the status data frames have been received from all the distributed type remote I/O units (step S
4
affirmative), then connection state of each distributed type remote I/O unit
2
is analyzed from the status data, and a result of analysis is displayed on the display unit
3
in the basic system of the NC unit
1
(step S
5
).
Then the MPU
101
in the basic system of the NC unit
1
switches the operating mode to the on-line communication mode, generates on-line transmission frames each including data outputted by the distributed type remote I/O unit
2
(step
6
), successively transmits the on-line transmission frame to the distributed type remote I/O units
2
(step S
7
), receives frames each including ordinary input data (on-line receiving frame) from the distributed type remote I/O units
2
(step
8
), and executes each analysis of receiving state (whether receiving is complete or not, and whether any error is included in the received data or not) as well as of received data (step
39
). Then, the operating sequence from step S
6
to step S
9
is repeated.
Next description is made for a software processing flow by the MPU
111
in the distributed type remote I/O unit
2
in the distributed type remote I/O numerical control system as described above.
Upon power turn ON, the MPU
111
in the distributed type remote I/O unit
2
executes a control program stored in the memory
113
to initialize operation of the communication control section
113
and read switch status data, recognizes how the unit
2
itself stands in a group of the distributed type I/O units
2
installed in the control system (step S
21
), and then enters the waiting state for receiving a transmission frame transmitted from the basic system of the NC control unit
1
to the distributed type remote I/O unit
2
(step S
22
). When the distributed type I/O units
2
receives a transmission frame transmitted thereto from the basic system of the NC unit
1
(step S
22
affirmative), the MPU
111
determines whether the frame is in the off-line communication mode or the on-line communication mode from the header pattern (step S
23
).
In the off-line communication mode, namely if a status data request frame has been received, status data for the distri

Affiliated with

Also associated with

Rating

Control method for distributed type remote I/O control... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Control method for distributed type remote I/O control..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Control method for distributed type remote I/O control... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2488509