INSTRUMENTATION CONTROL SYSTEM

• US 20090287322A1
• Filed: 05/06/2009
• Published: 11/19/2009
• Est. Priority Date: 05/15/2008
• Status: Abandoned Application

• Current Assignee: Yokogawa Electric Corporation
• Original Assignee: Yokogawa Electric Corporation
• Inventors: ENDO, Masahito, Hosoya, Kensuke, Endo, Hiroki, Akisada, Yukiyo, Miyata, Hiroshi
• Application Number:
  US12/436,479
• Publication Number:
  US 20090287322A1
• Time in Patent Office: Days
• US Class Current: 700/81
• CPC Class Codes: G05B 19/0428 Safety, monitoring G05B19/0423 takes precedence
• CPC Class Codes: G05B 2219/25154 Detect error, repeat transmission on error, retransmit

Abstract

Disclosed is an instrumentation control system, including: a first field device; and a second field device coupled to the first field device via a fieldbus. The first field device includes: a transmitting buffer to store data to be transmitted; a transmitter; and an inquiry processing section to cause the transmitter to retransmit the data stored in the transmitting buffer to the second field device in response to a request from the second field device. The second field device includes: a receiving buffer to store the data transmitted from the first field device; a checking section to determine whether the data stored in the receiving buffer is normal or not, and to make a data retransmission request to the first field device if the data stored in the receiving buffer is not normal; and a processing unit to perform predetermined processing based on the data which is determined to be normal.

Claims

1. An instrumentation control system, comprising:

a first field device; and

a second field device coupled to the first field device via a fieldbus to allow bidirectional communication, wherein the first field device comprises;

a transmitting buffer to store data to be transmitted to the second field device;

a transmitter to transmit the data to the second field device; and

an inquiry processing section to cause the transmitter to retransmit the data stored in the transmitting buffer to the second field device in response to a data retransmission request from the second field device, and the second field device comprises;

a receiving buffer to store the data transmitted from the first field device;

a checking section to determine whether the data stored in the receiving buffer is normal or not, and to make a data retransmission request to the first field device if the data stored in the receiving buffer is not normal; and

a processing unit to perform predetermined processing based on the data which is determined to be normal by the checking section.

2. The instrumentation control system according to claim 1, wherein

the transmitter of the first field device periodically transmits the data stored in the transmitting buffer to the second field device, and

the processing unit of the second field device periodically performs the predetermined processing based on the data transmitted from the first field device.

3. The instrumentation control system according to claim 1, wherein

the first field device further comprises an identifier adding section to add an identifier for discriminating from other data, to the data to be transmitted to the second field device,

the transmitter transmits the data with the identifier to the second field device,

the receiving buffer of the second field device stores the data with the identifier transmitted from the transmitter, the identifier being a first identifier,

the second field device further comprises a storage unit to store an identifier as a second identifier that is added to the data which is determined to be normal by the checking section, and

the checking section compares the first identifier included in the data with the identifier stored in the receiving buffer, with the second identifier stored in the storage unit to determine whether the data with the first identifier is normal or not.

4. The instrumentation control system according to claim 1, wherein

the checking section requests the first field device to retransmit data and specifies retransmission time of the data, and

the inquiry processing section causes the transmitter to retransmit the data at the retransmission time.

5. The instrumentation control system according to claim 1, wherein

the checking section makes a data retransmission request to the first field device and gives the first field device an instruction to retransmit subsequent data to be transmitted, and

the inquiry processing section causes the transmitter to retransmit the subsequent data without the data retransmission request once the instruction to retransmit the subsequent data is received.

6. The instrumentation control system according to claim 1, wherein

the checking section makes a data retransmission request with authentication information indicating that the data retransmission is requested from the second field device, and

the inquiry processing section causes the transmitter to retransmit the data to the second field device when the data retransmission request from the second field device is authenticated based on the authentication information.

7. The instrumentation control system according to claim 1, wherein

the first field device further comprises a sensor to acquire measurement data,

the transmitter transmits the measurement data to the second field device, and

the processing unit of the second field device performs the predetermined processing based on the measurement data which is determined to be normal by the checking section.

8. The instrumentation control system according to claim 7, wherein

the inquiry processing section causes the transmitting buffer to store measurement data newly acquired by the sensor and causes the transmitter to retransmit the measurement data, in response to the data retransmission request from the second field device.

9. The instrumentation control system according to claim 1, wherein

the first field device comprises a first history storage unit to store a history of data transmitted to the second field device,

the second field device comprises a second history storage unit to store a history of data which is determined to be normal by the checking section,

the checking section specifies missing data with reference to the history stored in the second history storage unit, and makes a retransmission request of the missing data to the first field device, and

the inquiry processing section causes the transmitter to transmit data stored in the first history storage unit in response to the retransmission request.