Modbus Repeater with Self-Adaptive Baud Rate Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing Modbus repeaters require manual setting of baud rate and encoding mode, lack remote automatic detection capabilities, and are inconvenient for remote control applications, limiting their adaptability and flexibility.
Innovation Solution
A self-adaptive baud rate system utilizing a Complex Programmable Logic Device (CPLD) and an external crystal oscillator to automatically detect and adjust baud rate and encoding format in Modbus communications, enhancing flexibility and stability by controlling RS485 transceivers through a baud rate generator and counters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If manual setting of baud rate and encoding mode is used, then device complexity is reduced, but adaptability and ease of operation deteriorate
Solution Approach 1:
The system performs self-identification of communication parameters by automatically detecting baud rate and encoding mode through hardware circuits, eliminating the need for manual configuration while maintaining adaptability across different communication protocols
Solution Approach 2:
The patent replaces manual mechanical adjustment (rotary encoder) with automated electronic detection circuits that use counters and logic circuits to identify communication parameters, reducing operational complexity while improving adaptability
2Ease of operation
If manual operation is used, then device complexity is reduced, but ease of operation deteriorates
Solution Approach 1:
The system automatically detects and identifies communication parameters without requiring user intervention, making the device easier to operate while the internal hardware circuits manage the complexity of detection and identification
Solution Approach 2:
The hardware circuits are pre-configured with detection logic that automatically executes parameter identification upon connection, performing necessary actions before user operation begins and eliminating manual configuration steps
3Adaptability or versatility
If rotary encoder is used for manual setting, then device complexity is reduced, but adaptability deteriorates
Solution Approach 1:
The patent replaces the mechanical rotary encoder with electronic detection circuits comprising counters and logic circuits that automatically identify communication parameters, enabling adaptability to multiple protocols while managing device complexity through integrated hardware design
Solution Approach 2:
The detection circuit is designed to universally identify different baud rates and encoding modes through a single integrated system, allowing the device to adapt to various communication protocols without requiring separate configuration mechanisms for each protocol type
Data Source
Figure 1~3
Figure 4
Figure 5~6
AI summary
Disclosed are a self-adaptive baud rate system and method. The method includes: a) receiving first data and second data; b) judging whether or not a falling edge of a start bit in a synchronization code of the first data and second data is detected; c) if the falling edge is not detected, then return to step b); and if the falling edge is detected, then a first counting is started from a rising edge after the start bit based on a reference clock, and stopped at the next falling edge, and a first count value is obtained; and a second counting is started from the falling edge where the first counting was stopped, and stopped at the next rising edge, and a second count value is obtained; and d) acquiring a baud rate according to the relationships among the first count value and the second count value and a first threshold. By way of using a CPLD to detect the baud rate and encoding format of a Modbus data frame remotely according to the present application, there is no need to manually set the baud rate and encoding format locally. The function of remote auto-detection of the baud rate and encoding format can be achieved by the present application, and the materials and assembly costs of the rotary encoder are omitted.