The ISO7220 and ISO7221 are dual-channel digital isolators. To facilitate PCB layout, the channels are orientedin the same direction in the ISO7220 and in opposite directions in the ISO7221. These devices have a logic inputand output buffer separated by TI’s silicon-dioxide (SiO2) isolation barrier, providing galvanic isolation of up to4000 V. Used in conjunction with isolated power supplies, these devices block high voltage, isolate grounds, andprevent noise currents on a data bus or other circuits from entering the local ground and interfering with ordamaging sensitive circuitry.
The C500 microcontroller family usually provides only one on-chip synchronous serialchannel (SSC). If a second SSC is required, an emulation of the missing interface mayhelp to avoid an external hardware solution with additional electronic components.The solution presented in this paper and in the attached source files emulates the mostimportant SSC functions by using optimized SW routines with a performance up to 25KBaud in Slave Mode with half duplex transmission and an overhead less than 60% atSAB C513 with 12 MHz. Due to the implementation in C this performance is not the limitof the chip. A pure implementation in assembler will result in a strong reduction of theCPU load and therefore increase the maximum speed of the interface. In addition,microcontrollers like the SAB C505 will speed up the interface by a factor of two becauseof an optimized architecture compared with the SAB C513.Moreover, this solution lays stress on using as few on-chip hardware resources aspossible. A more excessive consumption of those resources will result in a highermaximum speed of the emulated interface.Due to the restricted performance of an 8 bit microcontroller a pin compatible solution isprovided only; the internal register based programming interface is replaced by a set ofsubroutine calls.The attached source files also contain a test shell, which demonstrates how to exchangeinformation between an on-chip HW-SSC and the emulated SW-SSC via 5 external wiresin different operation modes. It is based on the SAB C513 (Siemens 8 bit microcontroller).A table with load measurements is presented to give an indication for the fraction of CPUperformance required by software for emulating the SSC.
The solution presented in this paper and in the attached source files emulates the mostimportant SSC functions by using SW routines implemented in C. The code is focused onthe SAB C513, but will fit to all C500 derivatives.Beyond the low level software drivers a test shell is delivered. This shell allows a quicktest of the software drivers by an emulator or a starter kit demo board.
基于P87 C591的CAN總線系統智能節點設計Design of CAN System Intelligent Node Based on P87C591
給出了基于帶CAN控制器的單片8位微控制器P87C591的智能節點的硬件電路及軟件結構,詳細介紹了設計中的難點及實現過程中應注意的問題。關鍵詞:CAN總線;智能節點
Abstract:A h ardc ircuita nds oftw arec onfigurationo fth ei ntelligentnode based on a microcontroller with CAN controller P87C591 arepresented.E speciallyt hec ruxi nd esigninga ndt hep roblemst hatshould be paid attention in realizing are discussed in details.Keyw ords:C AN;in telligentn ode
CA N 總線 是德國Bosch從20世紀80年代初為解決現代汽車中眾多的控制與測試儀器之間的數據交換而開發的一種串行數據通信協議,它是一種多主總線,通信介質可以是雙絞線、同軸電纜或光導纖維。由于CAN總線具有較強的糾錯能力,支持差分收發,因而適合高噪聲環境。并具有較遠的傳輸距離,適用于許多領域的分布式測控系統。目前已在工業自動化、建筑物環境控制、醫療設備等許多領域得到廣泛的應用。CAN已成為國際標準化組織IS011898標準。
針對使用硬件描述語言進行設計存在的問題,提出一種基于FPGA并采用DSP Builder作為設計工具的數字信號處理器設計方法。并按照Matlab/Simulink/DSP Builder/QuartusⅡ設計流程,設計了一個12階FIR 低通數字濾波器,通過Quartus 時序仿真及嵌入式邏輯分析儀SignalTapⅡ硬件測試對設計進行了驗證。結果表明,所設計的FIR 濾波器功能正確,性能良好。
Abstract:
Aiming at the problems in designing DSP using HDL,a method of designing DSP based on FPGA which using DSP Builder as designed tool is pointed out.A 12-order low-pass FIR digital filter was designed according to the process of Matlab/Simulink/DSP Builder/QuartusⅡ, and the design was verified by the timing simulation based on QuartusⅡand practical test based on SignalTapⅡ. The result shows the designed filter is correct in function and good in performance.
Accurate measurement of the third order intercept pointfor low distortion IC products such as the LT5514 requirescertain precautions to be observed in the test setup andtesting procedure. The LT5514 linearity performance ishigh enough to push the test equipment and test set-up totheir limits. A method for accurate measurement of thirdorder intermodulation products, IM3, with standard testequipment is outlined below.It is also important to correctly interpret the LT5514specification with respect to ROUT, and the impact ofdemo-board transmission-line termination loss whenevaluating the linearity performance, as explained in theLT5514 Datasheet and in Note 1 of this document.
關于NETFLOW信息分析的軟件。 is a netflow analyzer. It uses MySQL database to store accounting information. Filters, used in the JFlowAnalyzer, allows very flexible classificate any kind of traffic and store it in the differend fields in database
This book is about the management of business processes. This is certainly
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zemax源碼:
This DLL models a standard ZEMAX surface type, either plane, sphere, or conic
The surface also demonstrates a user-defined apodization filter
The filter is defined as part of the real ray trace, case 5
The filter can be used at the stop to produce x-y Gaussian apodization similar to the Gaussian pupil apodization in ZEMAX but separate in x and y.
The amplitude apodization is of the form EXP[-(Gx(x/R)^2 + Gy(y/R)^2)]
The transmission is of the form EXP[-2(Gx(x/R)^2 + Gy(y/R)^2)]
where
x^2 + y^2 = r^2
R = semi-diameter
The tranmitted intensity is maximum in the center.
T is set to 0 if semi-diameter < 1e-10 to avoid division by zero.
%CHECKBOUNDS Move the initial point within the (valid) bounds.
% [X,LB,UB,X,FLAG] = CHECKBOUNDS(X0,LB,UB,nvars)
% checks that the upper and lower
% bounds are valid (LB <= UB) and the same length as X (pad with -inf/inf
% if necessary) warn if too long. Also make LB and UB vectors if not
% already.
% Finally, inf in LB or -inf in UB throws an error.