The control mode and principle of pneumatic valve pneumatic actuators ( 2)

X pin is arranged, SO the serial data output; < SI serial data input; < SCK serial clock output; < Write maintenance input WP. With a pin, the function of each pin is as follows:
CS circuit selection side, low level;
SO serial data output;
SI serial data input;
SCK serial clock output;
WP written maintenance input, low level;
RESET RESET output;
Vcc power supply side;
Vss earthing terminal.

because there are more and more control mode and means, the digital circuit partial mainly includes: single chip microcomputer, power-fail protection, two monitoring pulse input signal, two normally open normally closed switch contact output. < In use in the design of the current commonly used series microcontroller ATCATC a low voltage, high performance CMOS microcontroller. Real industrial raw and industrial control, often used to control the pneumatic actuators method are many, there are several commonly used. A

intelligent display control based on single chip microcomputer development intelligent display is used to working state monitoring of pneumatic valve, pneumatic valve opening and control work of the instrument, through two lines of position sensor to monitor the working state of the pneumatic valve, judgment of pneumatic valve is in a state of pneumatic valve open or close the pneumatic valve, pneumatic digital valve switch, through programming records and two road and pneumatic valve opening corresponding mA output and output bipedal normally open normally closed contacts. Through these output signals, the pneumatic valve control action. According to the requirement of the system, intelligent pneumatic valves on the display, from hardware can be divided into partial to design: simulation of local/display, digital local, buttons.
local main analog circuit including power supply, analog input circuit, analog output circuit three parts.
power supply of local energy, the whole circuit includes analog circuit, digital circuit and display of energy supply. In order to realize the remote control, pneumatic valve open read to the pneumatic valve opening information transmitted to other control instrument, control instrument can from a distance at the same time for a set of pneumatic valve opening, the system needs to be mA mA analog input signals and road analog output signal. Analog input signal by A/D conversion into pneumatic valve opening and the corresponding digital signal to local MCU, MCU in it filter can output after the disposal of the pneumatic valve opening information through D/A converted into analog signal output, is used to connect display shows pneumatic valve opening or connect to other control equipment. This design system, all of the amount of digital data are adopts serial input and output method, in order to save the chip resource and space, the input of the mA analog when converted to digital quantity, use of the existing road DA chip combined with single chip computer system resources used for an AD.
local digital circuit mainly includes: single chip microcomputer, power-fail protection, two monitoring pulse input signal, two normally open normally closed switch contact output.
in use in the design of the current widespread use of series microcontroller ATCATC a low voltage, high performance CMOS microcontroller, with K bytes can be erased, repeatable read only memory programming. By composite in the single chip a multi-function a flash memory, CPU performance, instruction set and fully compatible with C and C on the pin.
needs to insist on previous set some parameters of the pneumatic valve in the instrument, considering the system power down or reboot. And single chip microcomputer the data in the memory don't have electricity storage function, so in the slice extends outside a chip XX has off electricity saving function set a guard dog, power monitoring and block serial EEPROM circuit of programmable functions in one, this combination design can reduce the demand for printed circuit board space circuits, watchdog for the system of X provides maintenance, when the system sends the fault and beyond the setting time, the watchdog circuit will be reaction through the RESET signal to CPU. X provides three time value for users to choose to use. Of voltage monitoring function can also maintain system from the effects of low voltage, when the power supply voltage to allow the following system will be reset, until the power supply voltage returns to the stable value. X memory and CPU interface by way of serial communication. Altogether, can place data in bytes.