The coder decipher interface that is based on CPLD reachs his to control the application in card and servo driver in motion

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Foreword is in numerical control machine tool or equipment of other numerical control, often can use the position such as grating feet or coder pass move part, in order to will measure the virtual campaign position of mechanical movement component and rate news. So the numerical value that grating feet or coder measure, with respect to reception the part is handled. The signal that general coder outputs is AB (or ABZ) signal of photograph orthogonality encode, coding so also is to add directional information the code to flow, at the same time the processing of the respect such as advantageous also interference rejection. Need special decipher interface circuit when receiving this signal accordingly, move the data of earning actually namely the position / positional information delivers processing unit, or pass bus line (for instance PCI) in the system is being controlled in the center of deliver numerical control equipment, the real message that the soft hardware that lets control a system comes to according to measuring and ideal (logistic) information undertakes contrast, adjust next according to relative error result again the position of athletic component and speed, or do other interrupt, the outputs a movement to control mechanical movement in order to achieve purpose of switch sex. Even, through complete algorithm brings into the information such as the position, speed, moment of force come in the system, do processing of real time feedback, this namely the closed circuit that we say (half closed circuit) processing, our common algorithm is PID (or PI) algorithmic. Such since, go to the lavatory to run make known to lower levels full automaticly to fast, accurate, soft character at letting mechanical equipment be in quite. One, will realize coder decipher interface and PWM output function with CPLD there has been appropriative coder signal on market now / chip of interface of decipher of signal of encode of AB photograph orthogonality, basically be Euramerican the chip that waits for a country to offer, for instance the product such as HCTL-2016/HCTL-2020. But these product performance/price ratio are poorer still, the function is not quite rich, use rise to also do not go to the lavatory neatly, fit the requirement of broad client very hard. And the design that the CPLD of the dimensions in using will come to fulfil function of decipher of signal of encode of AB photograph orthogonality, became an option, the plasticity of together with CPLD, reach the sexual price that has taken increasingly to compare a trend, this kind of plan made only best choice even. General situation, the CPLD of the market main trend of Altera/Lattice/Xilinx can satisfy the requirement of the design, logic is in medium dimensions, brief 500-1000 grand unit, can fulfil function of decipher of signal of encode of orthogonality of photograph of AB of 1-4 passageway decipher, and the PWM of passageway of OK and adscititious 1-4 happens, and the patulous function of I/O of multichannel number amount. Perhaps finish decipher of photograph of 1-4 axis AB adscititious but process designing pulse produces a function. And should make full use of the resource of CPLD, and achieve the design of a high-powered, high reliability, need enough technical force safeguard, such ability can have tall sex to add compared product to appear. Limited company of development of Shenzhen city Si Maidi science and technology is formal such company, major is engaged in motion controlling SOPC (namely CPLD, FPGA) program of chip class technology and development of program of platform class technology, roll out many motion to control SOPC chip product to the market. Among them the decipher of the signal of ABZ photograph coder that SM2100 series is 1-4 road and product of SOPC of PWM output function. 2, the functional introduction that is 2100 series below 2.

The function that the ABZ photograph decipher that SM2100 of 1SM2100 characteristic brief introduction offerred 1-4 channel, 4 times frequency, 16 coder computation limits and 16 PWM pulse produce. Added in chip interior at the same time 8 general inputs and 8 current output. Because chip is SOPC technology program, because this is returned,can do according to specific requirement of the client directional the design that change. Graph 1 SM2100 functional-block diagram pursues 1 it is its functional-block diagram. Its function index is below: Bell CLK frequency is highest when the input to 80MHz, the standard inputs frequency 40MHz; Of PWM occupy sky comparing adjusting range 0 ～ 4095, 150KHz of ～ of 150Hz of frequency adjusting range; 16 coder tally, can amount to computation limits to be: 1 ～ 65535; AB photograph is inputted but 4 times frequency, AB is received inside the input 3 rank the number is small connect colander, filter wave bandwidth 4 class are adjustable. 2.

The design application of 2SM2100 explains SM2100 is plan of a SOPC, its applied characteristic goes to the lavatory euqally as common ASIC, through 8 CPU interface and advocate accuse interface of parts of an apparatus, will install its job status and function through in-house register. Among them CPU interface is very simple: Bus line of 8 two-way data: D0 ～ 7; 7 addresses bus line: A0 ～ 6; 1 piece choose a route: CS_n; 1 reads allow a line: RD_n; 1 writes allow a line: WR_n. Also can need according to the user, offer port of 16 bus line. Increase to 16 besides data bus line outside, other signal and interface of 8 bus line are identical. Introduction of main functional setting register is below. Pass the description of these register, applied engineers can look the particular function that sees SM2100 like that clear is reached how to use. 2.

The graph below function of computation of decipher of the main function principle of 3SM2100 and applied introduction A, coder the 2 principles that are decipher computation part: Graph the principle SM2100 chip of part of 2 decipher computation has 1-4 channel tally of coder of 16 ABZ photograph. The computation register that takes each channel through reading (CNT ＊ ) can get the count with this current passageway is worth. The register of computation to clear to each passageway (CNT ＊ _CLR) the computation register to clear that writes an operation to will this. The input end of every tally has 4 times frequency circuit and 3 rank digital filter circuit. The bandwidth of digital filter divides 4 shelf adjustable, it is 10M respectively, 5M, 2.

5M, 625K, it is OK to part the width that goes up except ABZ photograph signal is less than filter 300ns, 600ns, 1.

2us, 4.

The interference of 8us. To mode register (MODE) write an operation to be able to part set the filter bandwidth of each passageway. The ascendant edge of date believes in Z, can lock up current coder computation value existence index register (CNT ＊ _IDX) in, at the same time condition register (STATUS) medium corresponding mark position 1. CPU chip can be mixed according to the condition register of SM2103 the value of index register undertakes answering was handlinged at 0 o'clock. The index of condition register indicates an automatic after condition register reads an operation to clear. Chip of SM2100 of output of B, PWM has 1-4 channel 16 PWM output. Use at generation complementary (poor cent) signal of wide modulation of arteries and veins has dead band to control a function. The in controlling the electric machinery that finish power drive that can use pair of 3 phasic transistor and function of 3 photographs inverter, OK also or band is small the DA of the wave that connect filter that finish changes a function. The cycle of PWM output pulse can connect associate with to control register PWM_TL, PWM_TH to write data to install. Available data is 16, namely 8 of PWM_TL with PWM_TH low 4. The pulse width of N passageway can connect associate with to control register PWM_WnL, PWM_WnH to write data to install. Available data is 16, namely 8 of PWM_WnL with PWM_WnH low 4. The lowest toward PWM_EN register write 1 when, make can PWM; Write 0 when, prohibit PWM is outputted (output 0 n) . When the setting that is more than pulse cycle when the setting of PWM pulse width is worth, output pulse occupy sky comparing to maintain for 100% . What C, general IO uses pair of SM2100 chip is general input-output operation, undertake reading writing to register of GPI, GPO directly can. This function can use the switch in didymous system to measure control, or the I/O in be similar to PLC nods control. 3, the applied plan citing of 2100 introduces 3.

1SM2100 chip controls calorie of medium application in motion: Be based on the reading of PCI to block SMP330SMP330 is to use the 3 passageways AB of the 32 PCI bus line that SM2103 and design of PCI interface chip give photograph decipher computation and PWM output get stuck. This calories apply to electric machinery control, the position in system of numerical control machine is monitored. It reflected all functional characteristics of afore-mentioned SM2100 series chip, include 3 channels tally of encode of 16 A/B photograph, 3 16 PWM signal are outputted, with passageway of the digital input with general multichannel, output. Because be the product of board card level, because this still made systematic property circuit,recuperate processing. For example coder signal interface uses the input that need branch to receive, high speed photoelectricity is kept apart; PWM output passes output of 74LS06 chip OC; The output input that the number measures passes photoelectricity segregation, output among them still be in charge of through Dalindu increase drive electric current; In addition still be in board on increased to keep apart power source module, in order to increases interference rejection sex of the system. Pursue below the 3 systematic functional-block diagram that are SMP330: Graph card can use the SMP330 of 3 block diagram of construction of system that are SMP330 to many application domain: Procedure of surveillance of electric machinery control, process, industry is controlled. Have specificly: The machine that copy number, measure an analysis instrument, semi-automatic change number of fixed position machine, PC to show etc. It can fulfil the reading function in the system, be opposite namely real position / the measurement of rate news, advantageous still undertake controlling to electric machinery with PWM function, at the same time digital GPI/O function also can use pair of systems to undertake I/O expands. Copy several machine for instance. We are in the design production of real work, to the mechanical exterior of a few more complex or irregular workpiece the design compares difficulty, special also need is time-consuming at the same time. Below this kind of circumstance, if have real referenced in kind, the position that uses the machine that copy number explores place fast to the real position information of the crust of objective and the measuring with accurate essence is gotten, use measures data to restore to give its directly " appearance " come, be being designed is one is modelled on efficiently quickly. So the main processing unit in equipment of this aircraft that copy number can use SMP330 card to come true. 3.

2SM2100 chip has had partial client to use SM2100 chip plan to realize product of its servo driver in the application in digital servo driver, the function is handled in the interface that speed and position take on in the product, and the function that outputs generation to PWM. Brush driver of dc number servo in order to not have to be here exemple. One controls principle block diagram to be able to use next figures without what brush dc machine 4 will express. Graph 4 control block diagram without what brush dc machine if we pursue to going up 3 undertake deep the complete digitlization circuit of one pace designs sexual fractionize, the picture that can get as follows functional-block diagram of servo of 5 numbers dc: Graph block diagram of servo of 5 numbers dc so, going up graph 5 in part of body of orchid quality circle can use plan of SM2100 series chip to come true, the function inside gray casing limits can use DSP or FPGA comes true, form plan of servo of a total number so. It is of course in this system, SM2100 just is become but partial function and interface, the closed circuit algorithm of main body is handled is come true in DSP or FPGA (coming true with FPGA plan also is Shenzhen city one of products of limited company of development of Si Maidi science and technology, its include 2100 inside, the characteristic that mainer is new-style FPGA makes will have original advantage compared with DSP plan, here no longer give uncecessary details) . Inside such plan, combinative SM2100 will come true, the advantage is it is good to increase systematic dependability, performance. The place on put together is narrated, servo of dc of a number (driver) processing comes true partly, can combine chip of a SM2100 to be finished with a DSP. CNC Milling