We will now look at the click plc modbus ascii protocol. This communication will happen in PLC ladder logic and communicate through the serial port (RS485) to a Solo process temperature controller. Modbus ASCII will be the communication protocol.
Modbus is a communication method used for transmitting information over serial lines between electronic devices. The device requesting the information is called the Modbus Master (Client) and the devices supplying information are Modbus Slaves (Servers). This protocol was originally developed by Modicon systems.
Modbus protocol comes in basically three different types. Ethernet (Modbus TCP) or Serial (Modbus RTU or Modbus ASCII). Modbus TCP and Modbus RTU come as standard protocols in the productivity series of PLCs.
We will connect the Click PLC to a Solo process temperature controller. This will be done using the Modbus ASCII protocol over serial RS485 communication wire. (Media) The present and set values (PV / SV) will be read from the Solo controller and the set value will be written when required. Let’s get started. Keep on Reading!
Time instructions in our productivity blocks programming (Arduino sketches) consist of runtime (ms), runtime (us), delay ms, and delay microseconds us.
We will be looking at each of these instructions that are available for our program using productivity blocks. Delay instructions in our sketches should be used with caution. They will pause our program for the delayed time, not allowing other parts of the program to function. We will be looking at this and the method to do the exact same delay functions without pausing your program.
A sample program will be discussed to demonstrate the time functions in our program. Let’s get started. Continue Reading!
Arduino programs (sketches) can be written in thousands of different ways. The best Arduino program control will be determined by the purpose of your program and what you are trying to accomplish. To simplify the logic we will be looking at program control that can be achieved using productivity blocks.
Program control will look at subroutines (sometimes referred to as methods or functions), conditional statements, and looping statements. These three items can be combined to reduce your code length, make your program easier to read, and in turn easier to troubleshoot.
We will be looking at each of these instructions that are available using productivity blocks. A sample program will then be discussed that will contain some program control as a demonstration. Let’s get started. Continue Reading!
We will now look at the BRX do-more plc ethernet remote IO. The BRX Do-More PLC has its own line of remote input and output expansion units. You can add up to 8 I/O expansion units per controller (CPU) and 8 BRX expansion modules per expansion unit. This will make your system grow with your needs.
The remote I/O expansion units feature the following:
• All units have built-in Ethernet port, 10/100 Mbps
• MBIO units have onboard RS-485 port with removable 3-Pin connector
• Support for 8 expansion modules
• AC and DC powered units available
• AC powered units include an integral 24VDC auxiliary output power supply
• Power connector and serial port connector included
We will be looking at the BX-DMIO-M. This is the Do-More Ethernet Remote I/O supported protocol unit. We will discuss the hardware and then connect and configure the unit to work with our existing BRX Do-more PLC. Let’s get started. Continue Reading!
We will now look at the Arduino serial monitor com. This serial communication is good for troubleshooting and displaying information to you or your operators. The Arduino integrated development environment (IDE) has a built-in pop-up serial monitor. The serial monitor can be used to receive and send serial data to our Arduino program. This can be a great feature to help us in debugging or controlling Arduino programs. (Sketches)
We will be modifying the blinking light program that we did previously and add a one to an integer every time the P1AM-100 arduino CPU switch is on. This will be then printed on the serial monitor.
Removing the blinking light, we will run our program again an see the difference in speed with the delay instructions removed. Productivity blocks will be used to program our industrial arduino controller.
We will then look at escape character codes that we can use with our industrial arduino. Since the built-in serial monitor will not interpret the escape codes, we will be using Putty as our serial monitor program. Let’s get started. Continue Reading!