Control system

• US 6,344,802 B1
• Filed: 02/28/2000
• Issued: 02/05/2002
• Est. Priority Date: 03/29/1999
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Watanabe, Hiroshi, Otsuka, Toru, Hashimoto, Takeo
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US09/514,361
• Time in Patent Office: 708 Days
• Field of Search: 340/825, 340/3.1, 340/3.31, 340/3.32, 340/3.44, 340/3.6, 340/3.5, 340/501, 340/511, 340/517, 700/10-12
• US Class Current: 340/3.1
• CPC Class Codes: G05B 19/0421 Multiprocessor system

Abstract

A control system is disclosed which permits information captured by each sensor to be sent exactly to a main controller and a fall in the level of sensor signals with time to be automatically compensated for with no need to make sensor signal lines long and without reducing the sensor monitoring accuracy and limiting the number of sensors used. The levels of signals from sensors connected to each of unit controllers are compared with slice levels. The results of comparisons are converted into a serial signal and then transmitted to the main controller. Each time the sensor signal level is monitored, the optimum slice level therefor is set.

Claims

1. A control system having a main controller and one or more unit controllers each of which has one or more sensors connected, comprising:

select means, provided in each of the unit controllers, for selecting sensor signals produced by the sensors in sequence;

comparison control means, provided in each of the unit controllers, for making a comparison between the level of a sensor signal produced by each of the sensors and a prestored threshold level and holding the result of each comparison;

control means, provided in each of the unit controllers, for converting the contents of the comparison control means into a serial signal and transmitting the serial signal to the main controller;

recognition means, provided in the main controller, for recognizing the results of comparisons sent in serial form from each of the unit controllers;

and slice level change means, controlled by said main controller, for changing the level stored in said comparison control means.

2. The control system according to claim 1, in which the comparison control means further includes an ON/OFF memory for storing an ON/OFF signal for each of the sensors as the result of a comparison between the level of a sensor signal produced by it and a prestored slice level.

3. The control system according to claim 1, in which the slice level change means further includes:

first control means provided in the main controller and having means for setting up a command to request a unit controller to transmit the levels of sensor signals produced by the sensors and transmitting that command to the unit controller;

first command execute means provided in each of the unit controllers and responsive to the command from the first control means for converting the levels of sensor signals produced by each of the sensors into a serial signal and transmitting the serial signal to the main controller;

second control means provided in the main controller and responsive to the levels of sensor signals transmitted from the unit controller for setting slice levels for the sensors, setting up a command to cause the slice levels to be held in the unit controller, and transmitting the command with conversion into a serial signal to the unit controller; and

second command execute means provided in each of the unit controllers for causing the slice levels as specified by the command sent from the second control means to be stored in the comparison control means.

4. The control system according to claim 3, further comprising:

control means provided in each of the unit controllers for, upon receipt of the command from the main controller, sending the same command back to the main controller; and

control means provided in the main controller and responsive to the command sent back from the unit controller for making an echo back check.

5. A control system having a main controller and a plurality of unit controllers each of which has a plurality of sensors connected, comprising:

select means, provided in each of the unit controllers, for selecting sensor signals produced by the sensors in sequence;

A/D conversion means, provided in each of the unit controllers, for converting the level of each of the sensor signals selected by the select means into digital data;

comparison control means, provided in each of the unit controllers, for making a comparison between output data of the A/D conversion means and prestored each of the slice levels for the sensors and holding the result of each comparison;

designate means, provided in the main controller, for designating each of the unit controllers;

control means, provided in each of the unit controllers, for, when the corresponding unit controller is designated by the designate means, converting the contents of the comparison control means into a serial signal and transmitting the serial signal to the main controller;

recognition means, provided in the main controller, for converting the results of comparisons sent in serial form from each of the unit controllers into parallel form and recognizing them;

and slice level change means, controlled by said main controller for changing the slice level stored in said comparison control means.

6. The control system according to claim 5, in which the comparison control means further includes an ON/OFF memory for storing an ON/OFF signal for each of the sensors as the result of a comparison between the output data of the A/D conversion means and a prestored each of the slice levels.

7. The control system according to claim 5, in which the slice level change means further includes:

first control means provided in the main controller and having means for setting up a command to request a unit controller designated by the designate means to transmit the output data of the A/D conversion means and transmitting that command with conversion into serial form to the designated unit controller;

first command execute means provided in each of the unit controllers and responsive to the command from the first control means for converting the output data of the A/D conversion means into a serial signal and transmitting the serial signal to the main controller;

second control means provided in the main controller and responsive to the data transmitted from the unit controller for setting each of slice levels for the sensors, setting up a command to cause the slice levels to be stored in the unit controller, and transmitting the command with conversion into a serial signal to the unit controller; and

second command execute means provided in each of the unit controllers for causing the slice levels as specified by the command sent from the second control means to be stored in the comparison control means.

8. The control system according to claim 7, further comprising:

control means provided in each of the unit controllers for, upon receipt of the command from the main controller, sending the same command back to the main controller; and

control means provided in the main controller and responsive to the command sent back from the unit controller for making an echo back check.

9. A control system having a main controller and a plurality of unit controllers each having one or more sensors connected and one or more output ports, comprising:

a sensor circuit, provided in each of the unit controllers, for transmitting sensor information serially over a first serial line to the main controller;

port information transmit means, provided in the main controller, for transmitting ON/OFF information for each of the output ports in each of the unit controllers over a second serial line to the unit controller;

an output port circuit provided in each of the unit controllers and responsive to the ON/OFF information for the output ports transmitted from the port information transmit means for performing ON/OFF control of each of the output ports; and

command transmit means provided in the main controller for transmitting a command signal for controlling the operating state of the sensor circuit and a command signal for controlling the operating state of the output port circuit over a third serial line to each of the unit controllers.

10. The control system according to claim 9, in which the sensor circuit includes:

select means for selecting a sensor output signal of each of the sensors in sequence;

an A/D converter for converting a sensor output signal selected by the select means into a digital signal;

storage means for storing threshold level information for each sensor;

compare means for making a comparison between the output data of the A/D converter for each of the sensors and the corresponding threshold level information stored in the storage means; and

sensor information transmit means for transmitting the result of the comparison by the compare means as sensor information over the first serial line to the main controller.

11. The control system according to claim 9, in which the unit controller further comprises a motor control circuit for controlling the movement of a motor and wherein the command transmit means transmits a command signal for controlling starting and stopping the motor over the third serial line to the unit controller.

12. The control system according to claim 11, in which the sensor circuit includes:

select means for selecting a sensor output signal of each of the sensors in sequence;

an A/D converter for converting a sensor output signal selected by the select means into a digital signal;

storage means for storing threshold level information for each sensor;

compare means for making a comparison between the output data of the A/D converter for each of the sensors and the corresponding threshold level information stored in the storage means; and

sensor information transmit means for transmitting the result of the comparison by the compare means as sensor information over the first serial line to the main controller.

13. The control system according to claim 9, wherein the unit controller further comprises response transmit means for transmitting a response of the result of execution of a command transmitted from the command transmit means over a fourth serial line to the main controller.

14. The control system according to claim 13, in which the sensor circuit includes:

select means for selecting a sensor output signal of each of the sensors in sequence;

an A/D converter for converting a sensor output signal selected by the select means into a digital signal;

storage means for storing threshold level information for each sensor;

compare means for making a comparison between the output data of the A/D converter for each of the sensors and the corresponding threshold level information stored in the storage means; and

sensor information transmit means for transmitting the result of the comparison by the compare means as sensor information over the first serial line to the main controller.

15. The control system according to claim 9, in which the unit controller further comprises a motor control circuit for controlling the movement of a motor and response transmit means for transmitting a response of the result of execution of a command transmitted from the command transmit means over a fourth serial line to the main controller and wherein the command transmit means transmits a command signal for controlling starting and stopping the motor over the third serial line to the unit controller.

16. The control system according to claim 15, in which the sensor circuit includes:

select means for selecting a sensor output signal of each of the sensors in sequence;

an A/D converter for converting a sensor output signal selected by the select means into a digital signal;

storage means for storing threshold level information for each sensor;

compare means for making a comparison between the output data of the A/D converter for each of the sensors and the corresponding threshold level information stored in the storage means; and

sensor information transmit means for transmitting the result of the comparison by the compare means as sensor information over the first serial line to the main controller.

17. In a control system having a main controller and one or more unit controllers having one or more output ports, each of the unit controllers includes:

clock generating means for generating a clock signal;

counter means for counting the clock signal and producing a forced OFF signal at the time when a preset clock count is reached;

ON/OFF information hold means for holding ON/OFF information for the output ports;

edge detect means for detecting a change in the ON/OFF information in the ON/OFF information hold means and providing a count enable signal to the counter means at the time when the change is detected; and

control means for instructing the counter means as to either whether to output,-the forced OFF signal or not or whether to count the clock signal or not according to an operation mode set by the main controller.

18. The control system according to claim 17, wherein each of the unit controllers further includes select means for making a selection among multiple clocks according to an operation mode set by the main controller and wherein the preset clock count in the counter means is set by the main controller.

19. The control system according to claim 17, wherein the main controller further includes designate means for designating each of the unit controllers in sequence and transmission control means for holding ON/OFF control information for the output ports of the unit controllers and transmitting ON/OFF information for the output ports of a unit controller designated by the designate means with conversion into a serial signal to the designated unit controller.

20. The control system according to claim 17, wherein the main controller further includes designate means for designating each of the unit controllers in sequence, transmission control means for holding ON/OFF control information for the output ports of the unit controllers and transmitting ON/OFF information for the output ports of a unit controller designated by the designate means with conversion into a serial signal to the designated unit controller, and each of the unit controllers further includes clock generating means for generating multiple clocks and select means for making a selection among multiple clocks according to an operation mode set by the main controller and wherein the preset clock count in the counter means is set by the main controller.

21. The control system according to claim 17, wherein the main controller further includes designate means for designating each of the unit controllers in sequence, information hold means for holding ON/OFF control information for the output ports of the unit controllers, transmission control means for transmitting ON/OFF information for the output ports of a unit controller designated by the designate means with conversion into a serial signal to the designated unit controller, and command hold and transmit means for holding a command to control the operation of each unit controller and transmitting it to the unit controller.

22. The control system according to claim 17, wherein the main controller further includes designate means for designating each of the unit controllers in sequence, information hold means for holding ON/OFF control information for the output ports of the unit controllers, transmission control means for transmitting ON/OFF information for the output ports of a unit controller designated by the designate means with conversion into a serial signal to the designated unit controller, and command hold and transmit means for holding a command to control the operation of each of the unit controllers and transmitting it to the corresponding unit controller, and each of the unit controllers further includes select means for making a selection among multiple clocks according to an operation mode set by the main controller, the preset clock count in the counter means being set by the main controller.

23. The control system according to claim 17, wherein the main controller includes designate means for designating each of the unit controllers in sequence, information hold means for holding ON/OFF control information for the output ports of the unit controllers, transmission control means for transmitting ON/OFF information for the output ports of a unit controller designated by the designate means with conversion into a serial signal to the designated unit controller, and command hold and transmit means for holding a command to control the operation of each unit controller and transmitting it to the unit controller, and each of the unit controllers includes:

output port means comprising clock generating means for generating a clock, counter means for counting the clock and producing a forced OFF signal at the time when a preset clock count is reached, ON/OFF information hold means for holding ON/OFF information for the output ports, edge detect means for detecting a change in the ON/OFF information in the ON/OFF information hold means and providing a count enable signal to the counter means at the time when the change is detected, and control means for instructing the counter means as to either whether to output the forced OFF signal or not or whether to count the clock or not according to an operation mode set by the main controller; and

operation result transmit means for holding the result of operation transmitted from the output port means and transmitting it to the main controller.

24. The control system according to claim 17, wherein the main controller includes designate means for designating each of the unit controllers in sequence, information hold means for holding ON/OFF control information for the output ports of the unit controllers, transmission control means for transmitting ON/OFF information for the output ports of a unit controller designated by the designate means with conversion into a serial signal to the designated unit controller, and command hold and transmit means for holding a command to control the operation of each unit controller and transmitting it to the unit controller, and each of the unit controllers includes:

output port means comprising clock generating means for generating a clock, counter means for counting the clock and producing a forced OFF signal at the time when a preset clock count is reached, ON/OFF information hold means for holding ON/OFF information for the output ports, edge detect means for detecting a change in the ON/OFF information in the ON/OFF information hold means and providing a count enable signal to the counter means at the time when the change is detected, control means for instructing the counter means as to either whether to output the forced OFF signal or not or whether to count the clock or not according to an operation mode set by the main controller, and select means for making a selection among multiple clocks according to an operation mode set by the main controller; and

operation result transmit means for holding the result of operation transmitted from the output port means and transmitting it to the main controller, the preset clock count in the counter means being set by the main controller.