A self-designed control of PC parallel port communication is introduced in this paper.Taking advantage of the MFC ActiveX technology, it is developed in Visual C++ and offset the scarcity of the control of PC parellel paort communication. An example of frequency measurement shows the detail procedure and application of the control.
The programming port of all the FP PLC’s support OPEN MEWTOCOL-COM. This is very useful when you want to monitor PLC values/bits or to set PLC values or bits via your COMPUTER. You can use any language such as Basic, C, Pascal, Assembler or even if other suppliers of PLCs can send ASCII strings, they can talk to our PLCs to exchange data.
water temperature control system uses the Single Chip Microcomputer to carry on temperature real-time gathering and controling. DS18B20, digitized temperature sensor, provides the temperature signal by "a main line". In -10~+85℃ the scope, DS18B20’s inherent measuring accuracy is 0.5 ℃. The water temperature real-time control system uses the electricity nichrome wire carring on temperature increiseament and operates the electric fan to realize the temperature decrease control. The system has the higher measuring accuracy and the control precision, it also can complete the elevation of temperature and the temperature decrease control.