ModLook - register scanner ModBus. We celebrate the 20th anniversary of the program
Today I would like to talk about the program with which I began to study the ModBus protocol and the PLC. I use it so far, and I personally saw it in use with several service engineers. If someone is interested in the history of its creation or source code please under the cat.
The ModBus register scanner is intended for people involved in setting up automation systems or simply trying to “make friends” with any device carrying Modbus. For those who want to be able to quickly read the registers of interest or manually walk through the contents of several devices on the bus.
The first author of the program is closely related to the process control system. The emergence of a PLC with ModBus in the 90s required some kind of program to work with this protocol. In those days, in order to view the contents of the controller registers, it was necessary either to install the controller programming environment on a computer, which is inconvenient, or to buy some kind of paid program. I wanted something light and compact that you can carry on a diskette. This led to the writing of its own program. The prototype of the program was written under Basic DOS. The prototype, by the way, was not very successful. Later the project was converted to Visual Basic. And somewhere in the early 2000s, the program was rewritten to Delphi. In the mid-2000s, the sources came to me. Then I rendered the ModBus survey to a separate stream, and added a few minor improvements. Recently added ModBus rtu polling mode over TCP / IP and converted the project to Lazarus.
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ModLook was written for own use. It turned out quite comfortable. All items are on the main panel. After measuring the parameter, you do not need to press OK, the changes are applied automatically. So the program can be operated with one hand (or foot).
For addressing data, register numbers are used (counting starts from 1), not physical addresses. Then it was more usual to start counting from one, and not from scratch.
ModLook can poll Coil Status (0XXXX), Discrete Inputs (1XXXX), Holding Registers (4XXXX), Input Registers (3XXXX). You can enable or disable polling of any of these registers by ticking “Poll”.
Link to source
The ModBus register scanner is intended for people involved in setting up automation systems or simply trying to “make friends” with any device carrying Modbus. For those who want to be able to quickly read the registers of interest or manually walk through the contents of several devices on the bus.
The first author of the program is closely related to the process control system. The emergence of a PLC with ModBus in the 90s required some kind of program to work with this protocol. In those days, in order to view the contents of the controller registers, it was necessary either to install the controller programming environment on a computer, which is inconvenient, or to buy some kind of paid program. I wanted something light and compact that you can carry on a diskette. This led to the writing of its own program. The prototype of the program was written under Basic DOS. The prototype, by the way, was not very successful. Later the project was converted to Visual Basic. And somewhere in the early 2000s, the program was rewritten to Delphi. In the mid-2000s, the sources came to me. Then I rendered the ModBus survey to a separate stream, and added a few minor improvements. Recently added ModBus rtu polling mode over TCP / IP and converted the project to Lazarus.
')
ModLook was written for own use. It turned out quite comfortable. All items are on the main panel. After measuring the parameter, you do not need to press OK, the changes are applied automatically. So the program can be operated with one hand (or foot).
For addressing data, register numbers are used (counting starts from 1), not physical addresses. Then it was more usual to start counting from one, and not from scratch.
ModLook can poll Coil Status (0XXXX), Discrete Inputs (1XXXX), Holding Registers (4XXXX), Input Registers (3XXXX). You can enable or disable polling of any of these registers by ticking “Poll”.
Link to source
Source: https://habr.com/ru/post/452164/
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