Advantages of the Controller Over Classic LPT

PLCM series controllers are specialized controllers for CNC systems and are designed to connect the CNC machine to a PC using modern interfaces such as Ethernet or USB.

The controller works with the PUMOTIX program and allows you to control 6 motors at the same time (in the current generation of PLCM controllers). The trajectory of movement is previously calculated in PUMOTIX, then the trajectory data is transferred to the PLCM buffer. Based on the data received, the controller independently generates Step/Dir control signals for motor drivers.

Advanced technologies make it possible to avoid the use of the outdated LPT interface, which ensures high noise immunity, stability, and it is possible to use modern personal computers and laptops to control the machine, placing them at a distance of up to 100 m from the machine (in case of Ethernet connection). The system requirements for the computer can be found in this article.

The proprietary software allows using the controller I/O ports in PUMOTIX instead of the LPT ports built into the PC. If you previously used the LPT port of the computer to connect the drivers, you will need to disconnect the connector from the LPT port of the computer, connect it to the PLCM controller and install PUMOTIX.

Each controller has at least one port that fully matches the physical LPT connector.

Principle of operation

The software of the PLCM series controllers is designed to minimize the load on your PC and transfer most of the machine control functions to the controller. The main task of the controller is to stabilize the frequency of formation of control Step pulses as much as possible. In addition, the controller performs many other functions that your PC previously performed.

For example, the controller has a built-in block for generating a control sequence for moving. This unit is used for manual control of the machine axes. When the user in PUMOTIX presses the move button, your PC sends to the controller a single command about the start of movement along a given axis in a given direction. The controller itself performs the movement, taking into account the overclocking profiles set by the user in the PUMOTIX settings.

Zero search and workpiece surface search are also completely performed by the PLCM without a PC. This is necessary to minimize the delay between the triggering of the position sensor and the stop of the tool.

All additional functions, such as processing end position sensors, checking the conditions of “soft” limits (Soft Limits), adjusting the height of the plasma cutting tool (THC), generating a PWM, enable signal, etc. they are also fully implemented by the controller’s internal software without the participation of control software that deals only with the interpretation of G-code.

Thanks to this approach, the computing load is almost completely removed from your PC, therefore, on the same computer during the execution of the G-Code, you can prepare new programs in CAM systems.