【正文】 , //frequency unsigned char phase, //phase unsigned char mode, //pattern unsigned char power //source ) The DAC0832 driven module In the design of the numerical control signal source, DAC0832 is defined as single buffered pattern, when the 8 bit Parallel data D0~D7 is input, the DA will transfer data in the CS. The bottom function of void DA0832(u8 value)can invoke Out_To_DDS0832(double Frequency,u8 type) function and control the defined wave form and frequency. This function is based on figure frequency poses principle, it transfers the input frequency into corresponding control word, and then bing phase stepbystep expect, output wave form data sheet in memory. The extent and dutyfactor can be tuned through invoking Adjust_Vpp() and Adjust Duty() Stepbystep automation procedure A stepbystep automation procedure brick is added to the design to define the frequency range, stepbystep rate , stepbystep amounts , ascending or lapse, cycling pattern. The stepbystep automation function can be realized through invoking Auto Step(AutoStepStr*AS) and passing memory structure type to a function. Test the experiment and data analysis The DDS numerical control signal source can import the various changeable control words by a touching screen, and then accurately control the signal frequency, dutyfactor, extent and phase. Figure 6 shows the corresponding experimental wave forms. Fig. 6 The oscillograph exports experiment picture (a) 1 KHz wave form output。 MCU。 b. Export the sine wave, sawtooth wave rectangular wave, triangle wave and arbitrarily wave form. c. Continuous Stepbystep adjustment of frequency, dutyfactor, extent and phase. d. The operation of the touching screen includes suppositional keyboard, sliding strip and various suppositional control carry out entering operation, and the every parameters can be demonstrated visually. e. Stepbystep automation, definition of: maximum value , minimum value , stepbystep rate , stepbystep amounts , ascending or lapse, cycling or not. Numerical control reform advantage of signal source The designed numerical control signal source is applied to the lathe reform experiment. The main targets of the numerical control system are the coordinate axis displacement (including displacement speed , direction , location etc.) , the control message originates from numerical control treating or moving control procedure mainly. Therefore, systematic the most fundamental position of the numerical control system should include three parts: The input/output procedure device, numerical control equipment and the servo drives. Conclusions Making pound use of DDS and MCU controller, the system can exported the numerical control signal source as the consumer need, it has the merits such as good exporting wave form, frequency accuracy, reliable stability and high dutyfactor. Each parameter and be easily adjusted by touching a screen, the experiments show that the various parametric indexes have fine numerical control effect. Acknowledgements This work was financially supported by the National Natural Science Foundation of China (No: 61006075) and Guided Projects on Integration of Production, Education and Research of Guangdong Province (No： 2020B090400253). References [1] Lygouras J. N., Tarchanidis K. N., Tsalides Ph. G., “Suspended Sediment and Dye Concentration Measurements Using a Digital Techniques”, Int. J. Electronics, 87, , pp 107, (2020). [2] Webster J. G. Ed., “Tactile Sensors for Robotics and Medicine”, Wiley, New York, (1988). [3] Dally J. W., Rilley W. F., Mcconnel ., “Instrumentation for Engineering Measurements”, Wiley, New York, (1993). [4] Tarchanidis K. N., Ioannidis I. N., Ka