SAINT

Keyword 2000 to RS-232 Gateway

01/20/04

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4 Message Format

To minimize latency with the RS-232 link, all data is sent in binary form. The same data format is used to send and receive messages. The gateway supports bi-directional asynchronous communications.

4.1Data Stream

The host data stream is broken into messages. A message consists of a Message ID and one or more data bytes.

The character FFh is used as an ESCAPE character to indicate the end of messages. There are three cases when an ESCAPE character is received.

If the ESCAPE character is followed immediately by a second ESCAPE character, the following are true:

∙The message is not yet complete.

∙The pair of ESCAPE characters represents a single byte of message data of value FFh.

If the ESCAPE character is followed immediately by a byte of value 00h, the following are true.

∙The message is complete.

∙Neither the FFh nor the 00h are part of the message.

∙No more messages are ready to be sent.

If the ESCAPE character is followed immediately by of any value other than FFh or 00h, the following are true:

∙The message is complete.

∙Neither the ESCAPE character nor the character following the ESCAPE character are part of the message.

∙The value following the ESCAPE character is the message ID for a new message.

This data stream format was chosen to allow arbitrary long messages (i.e. 4K Class 2 data blocks), to minimize the overhead to two bytes per message during peak traffic, and to immediately recognize the end of a message without having to wait for the next message to start.

After a gateway reset, the gateway will ignore all data until it sees an ESCAPE character. Once it has received a valid EOM, it will recognize the following message.

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Delphi Gateway Systems Analysis INterface Tool (SAINT), RS-232 manual Message Format, Data Stream
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Gateway Systems Analysis INterface Tool (SAINT), RS-232 specifications

Delphi Gateway Systems Analysis Interface Tool (SAINT) is a robust system that brings efficiency and precision to the analysis, monitoring, and management of data between disparate systems. Designed mainly for industrial settings where reliable communication is crucial, SAINT leverages the RS-232 communication standard, a long-established protocol that facilitates serial communication between devices.

One of the main features of SAINT is its ability to connect multiple devices through RS-232 interfaces, establishing a seamless data flow. This is particularly beneficial in environments where legacy systems still play a significant role. The tool utilizes the well-known characteristics of RS-232, such as point-to-point communication, which allows for straightforward setup and configuration. This makes it easy to connect various sensors, computers, and controllers that utilize RS-232 for data exchange.

Another critical feature of SAINT is its user-friendly interface, which enables operators to visualize data and manage connected devices effortlessly. Real-time monitoring and diagnostics are integral to the system, allowing users to detect anomalies or failures promptly. The tool also supports data logging, capturing historical data that can be analyzed for trends or performance evaluations, thereby enhancing decision-making processes.

In terms of technologies, SAINT is built on modern programming languages and frameworks, ensuring high levels of efficiency and scalability. The integration with existing systems is made easier through programmable logic, which allows for custom configurations tailored to specific operational requirements. This flexibility makes SAINT suitable for various applications, including manufacturing, transportation, and utility services.

The compatibility with multiple baud rates is another significant characteristic, providing users with the ability to adjust communication speed according to their needs. This compatibility, combined with built-in error-checking routines, enhances data integrity and system reliability.

Overall, Delphi Gateway Systems Analysis Interface Tool (SAINT) provides a comprehensive solution for seamless data integration across diverse platforms, making it an essential component in modern industrial communication setups. With its emphasis on RS-232 technology, user accessibility, and flexible integration options, SAINT is positioned as a leading tool for systems analysis and monitoring in a variety of operational environments.
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