CA1183246A - Three-way data switch for use in a control system for an automated work station - Google Patents
Three-way data switch for use in a control system for an automated work stationInfo
- Publication number
- CA1183246A CA1183246A CA000412462A CA412462A CA1183246A CA 1183246 A CA1183246 A CA 1183246A CA 000412462 A CA000412462 A CA 000412462A CA 412462 A CA412462 A CA 412462A CA 1183246 A CA1183246 A CA 1183246A
- Authority
- CA
- Canada
- Prior art keywords
- switching device
- data
- port
- bidirectional
- work station
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/18—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
- G05B19/408—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by data handling or data format, e.g. reading, buffering or conversion of data
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F13/00—Interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units
- G06F13/38—Information transfer, e.g. on bus
- G06F13/40—Bus structure
- G06F13/4004—Coupling between buses
- G06F13/4022—Coupling between buses using switching circuits, e.g. switching matrix, connection or expansion network
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/33—Director till display
- G05B2219/33185—Rs232c switch box, break out box, to connect different devices
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- General Engineering & Computer Science (AREA)
- Theoretical Computer Science (AREA)
- Human Computer Interaction (AREA)
- Manufacturing & Machinery (AREA)
- Automation & Control Theory (AREA)
- Mathematical Physics (AREA)
- Computer Hardware Design (AREA)
- Control By Computers (AREA)
Abstract
A THREE-WAY DATA SWITCH FOR USE IN A CONTROL SYSTEM
FOR AN AUTOMATED WORK STATION
Abstract of the Disclosure A control system for an automated work station comprises a data switching device having a first bidirectional port connected to a control computer, a second bidirectional port for connection to the controller of the work station and a third bidirectional port connected to an operator terminal. The switching device comprises logical circuitry responsive to signals from a manually operable mode selector circuit for interconnecting any selected pair of the ports. Other switch means on the device allow the monitoring at the operator terminal of the data transmitted between the computer and the work station controller.
FOR AN AUTOMATED WORK STATION
Abstract of the Disclosure A control system for an automated work station comprises a data switching device having a first bidirectional port connected to a control computer, a second bidirectional port for connection to the controller of the work station and a third bidirectional port connected to an operator terminal. The switching device comprises logical circuitry responsive to signals from a manually operable mode selector circuit for interconnecting any selected pair of the ports. Other switch means on the device allow the monitoring at the operator terminal of the data transmitted between the computer and the work station controller.
Description
The invention relates generally to a control sys~em for an automated work station and rnore particularly to a three-~la~ data communication switch for interconnecting a hos~ computer and an operator terminal to the work station controllerO
Robots are increasingly used in the manufacture of electronic equipment, particularly the electronic component assemb~y of printed circuit boards. Such a robot usually comprise a small special purpose computer or controller and a control terminal. The controller memory may be loaded with instructions defining the tasks to be accomplished by the robot. An operator terminal is connected to the communications port of the controller and is used to alter and/or add to the instructions in the controller rnemory.
It is very advantageous to be able to use a robot in cornbination with a CAD/CAM system (computer-aided design/computer-aided manufacturing). A CAD system is capable of capturing and formalizing a design from a designer. In the case of a printed circuit board, this is followed by automatic component placement and connection routing then generation of manufacturing data such as photo-mask and drill tape. To support this process, a CAD system has a comprehensive database in which the location of all the components on a printed circuit board are stored and this information rnay be supplied to a robot For its assembly task.
The host computer which runs the CAD system can be configured to drive a robot by composing robot programs each consisting of a series of discrete movernents and then load them into the robot's program rnernory, In addition, a host computer linked to a network of robots could perForm a variety of supervisory and backup functions such as robot task archiving and dispatching, cold start and bootstrapping, process control and synchronization, inventory control, and statistics gatherin~
As mentioned abovel a robot system controller comes equipped with a transmission port, usually using the EIA RS-232C transmission standard, for connection to a control terminal. However, there is often no provision for a second transmission port to which the host compu~er of a CAD system could be connected. Therefore, it is an object of this invention to provide a device which may be inserted into an exis~ing data transmission link to create in effect a second input transmission port to the robot controller thereby to permit its connection to both the CAD
system host computer and an operator terminal.
In accordance with the invention, there is provided a three-way switch adapted to be inserted into a data transmission line.
The switch comprises a first bidirectional port for connection to the communication port of a first computer via a first portion of the transmission line, a second bidirectional port for connection to the cornmunication port of a second computer via a second portion of the transmission line, and a third bidirectional port for connection to an operator terminal, said switch having logical circuitry operable under control of a switch means, for interconnecting any pair of the three bidirectional ports.
Basically, the invention provides a simple and economical switching device which, when inserted into a transmission line, provides an additional switched bidirectional port thereto as well as a selectable monitoring capability.
An example embodiment of the invention will now be described in conjunction with the drawings in which:
Figure 1 is a block diagram showing a control system for an automated work station including a three~ ay switching device, in accordance with the invention; and Figure 2 which is a logic schematic diagram of the switçhing device of figure 1.
Figure 1 illustrates a three-way switching device 10 having a first bidirectional port HR-HT connected to a host computer 11 via a first portion of transmission line 12. The computer 11 may be any one of a large variety of commercial units as for example model DEC-20 from Digital Equipment Corporation. The device 10 has a second bidirectional port CT-CR connected to the T port of a robot controller 13 via a second portion of transmission line 12. The T port of controller 13 normally supports the connection of an operator terminal such as 15 which may for example be a Regent Model 20 manufactured by Applied Digital Data Systems, Inc. The device 10 has a third bidirectional port TR-TT for connection to terminal 15. The robot controller 13 provides control signals to a robot 14 and together they comprise a commercial product available off-the-shelf and may for example consist of a robot model 560 manufac-tured by Unimation Inc. of Danbury, Connecticut. Transmission line 12 is one that meets the 2n requirements of EIA Standard RS-232C.
The device 10 may be inserted anywhere along the length of transmission line 12 and, as discussed below, may be switched to become transparent thereto. The device 10 thus effectively provides a second transmission dal;a port for the robot controller 13, allowing the connection of operator terminal 15 thereto. The terminal 15 may act as a data entry terminal to either the host computer 11 or the robot controller 13 or it may act simply as a monitor for the data transmitted between thern.
Figure 2 is a logic schematic diagram o-f the device 10. The data appearing on terminals TT, c-r, and HT appear at interface circuits 20, 21, and 22 which act as level translators for the data frorn units 1l, 13, and 15 to the level of the logic gates of switching device 10.
Similarly the -transmit interface circuits 23, 24, and 25 act as level translators and data drivers to their respective units 11, 13, and 15 from the switching device 10. The receive and transrnit circuits may be off-the-shelf circuits as for example Texas Instruments type SN75154 (receiver) and type SN75150 (driver). The AND gates 26 - 31 and OR gates lU 32 - 36 may be any suitable off-the-shelf components. The mode selector circuit 37 may conveniently be a Texas Instrument type SN74LS138 de oder circuit which responds to a combination of input levels to provide a HIGH
enable signal on one of leads CTE, CHE, or HTE; with switch SW1 in position 2, lead CHE is HIGH; with switch SW1 in position 3, lead HTE is HIGH. Of course, the functions of the mode selector circuit 37 could also be achieved through the use of a multiple contact, 3-position switch.
The Functions of the switching device 10 may be best understood by reference to a description of its operation.
With switch SW1 in position 1, lead CTE is at a HIGH level and yates 26 and 28 are enabled. The data transmitted by the operator terrninal 15 appears on terrninal TT and is fed to the robot controller 13 via interface circuit 20, gates 26 and 33, and interface circuit 24 to terminal CR. Similarly, the data transmitted from the controller 13 is received at the operator terminal 15 via terminal CT, circuit 21, gates 28, 32, and 35~ circuit 23 and terminal TR. Therefore, with the mode selector switch in position 1, an operator is able to communicate with the robot controller 13.
With the switch SW1 in position 3, lead HTE is HIGH and gates 27 and 30 are enabled. The data transrnitted by the operator terminal 15 is routed to the computer 11 via the circuit 20, gates 27 and 34, interface circuit 25, and terminal HR. Similarly, the data transrnitted by the computer 11 is routed to the operator terrninal 15 via circuit 22, gates 30, 32, and 35, interface circuit 23, and terminal TR.
Hence, with the mode selector switch SW1 in position 3, an operator can access the host computer 11 directly.
With the switch SW1 at position 2, lead CHE is HIGH and gates 29 and 31 are enabled. The data transmitted by the robot controller 13 is routed to the computer 11 via the receive interface circuit 21, gates 29 and 34, circuit 25, and terminal HR. Similarly, the data transmitted by the host computer 11 is routed to the controller 13 via the interface circuit 22, gates 31 and 33, circuit 24, and terminal CR. Thus, with switch SW1 in position 2, the computer 11 is connected to the controller 13 and the switching device 10 is transparent to the connection.
When the mode switch SW1 is in position 2, the terminal 15 may be used as a monitoring device to "listen in" on the communications between the cornputer 11 and the controller 13. With switch S'.12 operated, the data from the controller 13 is fed from the output of gate 29 through gates 36 and 35, and circuit 23 to the terminal 150 With switch SW3 operated, the data from the computer 11 is fed from the output of gate 31 through gates 36 and 35 and circuit 23 to the monitor terminal 15.
The invention provides a simple and economical data switch which rnay be inserted in the communication path between two data transceivers to provide for the connection of a third terminal. The mode setting of the switch rnay be selected to allow the terrninal to become interactive with either of the compui;ers or to simply serve as a monitoring device for the cornlnunications between them. It is envisaged that the host computer-monitor terminal combination could he used to control a plurality of work stations by simply switching the terminals CT-CR to any of the work stations.
Robots are increasingly used in the manufacture of electronic equipment, particularly the electronic component assemb~y of printed circuit boards. Such a robot usually comprise a small special purpose computer or controller and a control terminal. The controller memory may be loaded with instructions defining the tasks to be accomplished by the robot. An operator terminal is connected to the communications port of the controller and is used to alter and/or add to the instructions in the controller rnemory.
It is very advantageous to be able to use a robot in cornbination with a CAD/CAM system (computer-aided design/computer-aided manufacturing). A CAD system is capable of capturing and formalizing a design from a designer. In the case of a printed circuit board, this is followed by automatic component placement and connection routing then generation of manufacturing data such as photo-mask and drill tape. To support this process, a CAD system has a comprehensive database in which the location of all the components on a printed circuit board are stored and this information rnay be supplied to a robot For its assembly task.
The host computer which runs the CAD system can be configured to drive a robot by composing robot programs each consisting of a series of discrete movernents and then load them into the robot's program rnernory, In addition, a host computer linked to a network of robots could perForm a variety of supervisory and backup functions such as robot task archiving and dispatching, cold start and bootstrapping, process control and synchronization, inventory control, and statistics gatherin~
As mentioned abovel a robot system controller comes equipped with a transmission port, usually using the EIA RS-232C transmission standard, for connection to a control terminal. However, there is often no provision for a second transmission port to which the host compu~er of a CAD system could be connected. Therefore, it is an object of this invention to provide a device which may be inserted into an exis~ing data transmission link to create in effect a second input transmission port to the robot controller thereby to permit its connection to both the CAD
system host computer and an operator terminal.
In accordance with the invention, there is provided a three-way switch adapted to be inserted into a data transmission line.
The switch comprises a first bidirectional port for connection to the communication port of a first computer via a first portion of the transmission line, a second bidirectional port for connection to the cornmunication port of a second computer via a second portion of the transmission line, and a third bidirectional port for connection to an operator terminal, said switch having logical circuitry operable under control of a switch means, for interconnecting any pair of the three bidirectional ports.
Basically, the invention provides a simple and economical switching device which, when inserted into a transmission line, provides an additional switched bidirectional port thereto as well as a selectable monitoring capability.
An example embodiment of the invention will now be described in conjunction with the drawings in which:
Figure 1 is a block diagram showing a control system for an automated work station including a three~ ay switching device, in accordance with the invention; and Figure 2 which is a logic schematic diagram of the switçhing device of figure 1.
Figure 1 illustrates a three-way switching device 10 having a first bidirectional port HR-HT connected to a host computer 11 via a first portion of transmission line 12. The computer 11 may be any one of a large variety of commercial units as for example model DEC-20 from Digital Equipment Corporation. The device 10 has a second bidirectional port CT-CR connected to the T port of a robot controller 13 via a second portion of transmission line 12. The T port of controller 13 normally supports the connection of an operator terminal such as 15 which may for example be a Regent Model 20 manufactured by Applied Digital Data Systems, Inc. The device 10 has a third bidirectional port TR-TT for connection to terminal 15. The robot controller 13 provides control signals to a robot 14 and together they comprise a commercial product available off-the-shelf and may for example consist of a robot model 560 manufac-tured by Unimation Inc. of Danbury, Connecticut. Transmission line 12 is one that meets the 2n requirements of EIA Standard RS-232C.
The device 10 may be inserted anywhere along the length of transmission line 12 and, as discussed below, may be switched to become transparent thereto. The device 10 thus effectively provides a second transmission dal;a port for the robot controller 13, allowing the connection of operator terminal 15 thereto. The terminal 15 may act as a data entry terminal to either the host computer 11 or the robot controller 13 or it may act simply as a monitor for the data transmitted between thern.
Figure 2 is a logic schematic diagram o-f the device 10. The data appearing on terminals TT, c-r, and HT appear at interface circuits 20, 21, and 22 which act as level translators for the data frorn units 1l, 13, and 15 to the level of the logic gates of switching device 10.
Similarly the -transmit interface circuits 23, 24, and 25 act as level translators and data drivers to their respective units 11, 13, and 15 from the switching device 10. The receive and transrnit circuits may be off-the-shelf circuits as for example Texas Instruments type SN75154 (receiver) and type SN75150 (driver). The AND gates 26 - 31 and OR gates lU 32 - 36 may be any suitable off-the-shelf components. The mode selector circuit 37 may conveniently be a Texas Instrument type SN74LS138 de oder circuit which responds to a combination of input levels to provide a HIGH
enable signal on one of leads CTE, CHE, or HTE; with switch SW1 in position 2, lead CHE is HIGH; with switch SW1 in position 3, lead HTE is HIGH. Of course, the functions of the mode selector circuit 37 could also be achieved through the use of a multiple contact, 3-position switch.
The Functions of the switching device 10 may be best understood by reference to a description of its operation.
With switch SW1 in position 1, lead CTE is at a HIGH level and yates 26 and 28 are enabled. The data transmitted by the operator terrninal 15 appears on terrninal TT and is fed to the robot controller 13 via interface circuit 20, gates 26 and 33, and interface circuit 24 to terminal CR. Similarly, the data transmitted from the controller 13 is received at the operator terminal 15 via terminal CT, circuit 21, gates 28, 32, and 35~ circuit 23 and terminal TR. Therefore, with the mode selector switch in position 1, an operator is able to communicate with the robot controller 13.
With the switch SW1 in position 3, lead HTE is HIGH and gates 27 and 30 are enabled. The data transrnitted by the operator terminal 15 is routed to the computer 11 via the circuit 20, gates 27 and 34, interface circuit 25, and terminal HR. Similarly, the data transrnitted by the computer 11 is routed to the operator terrninal 15 via circuit 22, gates 30, 32, and 35, interface circuit 23, and terminal TR.
Hence, with the mode selector switch SW1 in position 3, an operator can access the host computer 11 directly.
With the switch SW1 at position 2, lead CHE is HIGH and gates 29 and 31 are enabled. The data transmitted by the robot controller 13 is routed to the computer 11 via the receive interface circuit 21, gates 29 and 34, circuit 25, and terminal HR. Similarly, the data transmitted by the host computer 11 is routed to the controller 13 via the interface circuit 22, gates 31 and 33, circuit 24, and terminal CR. Thus, with switch SW1 in position 2, the computer 11 is connected to the controller 13 and the switching device 10 is transparent to the connection.
When the mode switch SW1 is in position 2, the terminal 15 may be used as a monitoring device to "listen in" on the communications between the cornputer 11 and the controller 13. With switch S'.12 operated, the data from the controller 13 is fed from the output of gate 29 through gates 36 and 35, and circuit 23 to the terminal 150 With switch SW3 operated, the data from the computer 11 is fed from the output of gate 31 through gates 36 and 35 and circuit 23 to the monitor terminal 15.
The invention provides a simple and economical data switch which rnay be inserted in the communication path between two data transceivers to provide for the connection of a third terminal. The mode setting of the switch rnay be selected to allow the terrninal to become interactive with either of the compui;ers or to simply serve as a monitoring device for the cornlnunications between them. It is envisaged that the host computer-monitor terminal combination could he used to control a plurality of work stations by simply switching the terminals CT-CR to any of the work stations.
Claims (9)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A control system for an automated work station, said work station including a controller, the system comprising: a computer suitably programmed to communicate control information to said work station, an operator terminal, a data switching device having a first bidirectional port connected to said computer, a second bidirectional port for connection to said controller and a third bidirectional port connected to said operator terminal, said switching device comprising logical circuitry responsive to predetermined signals from a manually operable mode selector circuit for interconnecting any selected pair of said ports.
2, A control system as defined in claim 1 wherein the mode selector circuit is a logic decoder circuit responsive to predetermined settings of a manually operable switch means for generating enable signals each of which is operable to cause the logical circuitry to interconnect a respective pair of said ports.
3. A control system as defined in claim 2 wherein the switching device further comprises a pair of switches for providing enabling signals to logic gates whereby the data transmitted between the computer and the controller may be monitored at the operator terminal.
4. In a control system for an automated work station, the station including a controller and the system comprising a computer suitably programmed to communicate control information to the work station and an operator terminal, a data switching device having d first bi-directional port connected to said computer, a second bidirectional port for connection to said controller and a third bidirectional port connected to said operator terminal, said switching device comprising logical circuitry responsive to predetermined signals from a manually operable mode selector circuit for interconnecting any selected pair of said ports.
5. A data switching device as defined in claim 4 wherein the switch means is a mode selector circuit including a three-position switch operable to provide three mutually exclusive enable signals to said logical circuitry, each of said signals being operable to cause the interconnection of a respective pair of said three bidirectional ports.
6. A data switching device as defined in claim 5 and further comprising a switched logic circuit for allowing data received at said first or second port to be also received at said third port, whereby the data being transmitted between the first and second ports may be monitored at the third port.
7. A three-way switching device adapted to be inserted into a data transmission line, said switching device comprising a first bidirectional port for connection to a first data transceiver via a first portion of the transmission line, a second bidirectional port for connection to a second data transceiver via a second portion of the transmission line and a third bidirectional port for connection to an operator terminal, said switching device having logical circuitry operable, under control of a switch means for interconnecting any pair of the three bidirectional ports.
8. A three-way data transmission switching device as defined in claim 7 wherein the switch means is a mode selector circuit including a three-position switch operable to provide three mutually exclusive enable signals to said logical circuitry, each of said signals being operable to cause the interconnection of a respective pair of said three bidirectional ports.
9. A three-way data transmission switching device as defined in claim 8 and further comprising a switched logic circuit for allowing data received at said first or second port to be also received at said third port, whereby the data being transmitted on the transmission line may be monitored at the third port.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000412462A CA1183246A (en) | 1982-09-29 | 1982-09-29 | Three-way data switch for use in a control system for an automated work station |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000412462A CA1183246A (en) | 1982-09-29 | 1982-09-29 | Three-way data switch for use in a control system for an automated work station |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1183246A true CA1183246A (en) | 1985-02-26 |
Family
ID=4123685
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000412462A Expired CA1183246A (en) | 1982-09-29 | 1982-09-29 | Three-way data switch for use in a control system for an automated work station |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1183246A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0359064A2 (en) * | 1988-09-15 | 1990-03-21 | Hewlett-Packard Company | Computing system |
| EP2309395A1 (en) * | 2008-07-31 | 2011-04-13 | Actions Semiconductor Co., Ltd. | Method for realizing pins time share multiplexing and a system-on-a-chip |
-
1982
- 1982-09-29 CA CA000412462A patent/CA1183246A/en not_active Expired
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0359064A2 (en) * | 1988-09-15 | 1990-03-21 | Hewlett-Packard Company | Computing system |
| EP0359064A3 (en) * | 1988-09-15 | 1991-09-18 | Hewlett-Packard Company | Computing system |
| EP2309395A1 (en) * | 2008-07-31 | 2011-04-13 | Actions Semiconductor Co., Ltd. | Method for realizing pins time share multiplexing and a system-on-a-chip |
| EP2309395A4 (en) * | 2008-07-31 | 2011-08-31 | Actions Semiconductor Co Ltd | Method for realizing pins time share multiplexing and a system-on-a-chip |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEC | Expiry (correction) | ||
| MKEX | Expiry |