1、英文原文INTRODUCTION ABOUT ISISMany CAD users dismiss schematic capture as a necessary evil in the process of creating PCB layout but we have always disputed this point of view. With PCB layout now offering automation of both component placement and track routing, getting the design into the computer ca
2、n often be the most time consuming element of the exercise. And if you use circuit simulation to develop your ideas, you are going to spend even more time working on the schematic.ISIS has been created with this in mind. It has evolved over twelve years research and development and has been proven b
3、y thousands of users worldwide. The strength of its architecture has allowed us to integrate first conventional graph based simulation and now - with PROTEUS VSM - interactive circuit simulation into the design environment. For the first time ever it is possible to draw a complete circuit for a micr
4、o-controller based system and then test it interactively, all from within the same piece of software. Meanwhile, ISIS retains a host of features aimed at the PCB designer, so that the same design can be exported for production with ARES or other PCB layout software.For the educational user and engin
5、eering author, ISIS also excels at producing attractive schematics like you see in the magazines. It provides total control of drawing appearance in terms of line widths, fill styles, colours and fonts. In addition, a system of templates allows you to define a ouse style?and to copy the appearance o
6、f one drawing to another.Other general features include:?Runs on Windows 98/Me/2k/XP and later.?Automatic wire routing and dot placement/removal.?Powerful tools for selecting objects and assigning their properties.?Total support for buses including component pins, inter-sheet terminals, module ports
7、 and wires.?Bill of Materials and Electrical Rules Check reports.?Netlist outputs to suit all popular PCB layout tools.For the Power user ISIS incorporates a number of features which aid in the management of large designs. Indeed, a number of our customers have used it to produce designs containing
8、many thousands of components.?Hierarchical design with support for parameterized component values on sub-circuits.?Design Global Annotation allowing multiple instances of a sub-circuit to have different component references.?Automatic Annotation - the ability to number the components automatically.?
9、ASCII Data Import - .this facility provides the means to automatically bring component stock codes and costs into ISIS design or library files where they can then be incorporated or even totaled up in the Bill of Materials report.Users of ARES, or indeed other PCB software will find some of the foll
10、owing PCB design specific features of interest:?Sheet Global Net Properties which allow you to efficiently define a routing strategy for all the nets on a given sheet (e.g. a power supply needing POWER width tracks).?Physical terminals which provide the means to have the pins on a connector scattere
11、d all over a design.?Support for heterogeneous multi-element devices. For example, a relay device can have three elements called RELAY:A, RELAY:B and RELAY:C. RELAY:A is the coil whilst elements B and C are separate contacts. Each element can be placed individually wherever on the design is most con
12、venient.?Support for pin-swap and gate-swap. This includes both the ability to specify legal swaps in the ISIS library parts and the ability to back-annotate changes into a schematic.A visual packaging tool which shows the PCB footprint and its pin numbers alongside the list of pin names for the sch
13、ematic part. This facilitates easy and error free assignment of pin numbers to pin names. In additional, multiple packagings may be created for a single schematic part.A full chapter is provided on how to use ISIS and ARES together.ISIS provides the development environment for PROTEUS VSM, our revol
14、utionary interactive system level simulator. This product combines mixed mode circuit simulation, micro-processor models and interactive component models to allow the simulation of complete micro-controller based designs. ISIS provides the means to enter the design in the first place, the architectu
15、re for real time interactive simulation and a system for managing the source and object code associated with each project. In addition, a number of graph objects can be placed on the schematic to enable conventional time, frequency and swept variable simulation to be performed.Major features of PROT
16、EUS VSM include:?True Mixed Mode simulation based on Berkeley SPICE3F5 with extensions for digital simulation and true mixed mode operation.?Support for both interactive and graph based simulation.?CPU Models available for popular microcontrollers such as the PIC and 8051 series.?Interactive peripheral models include LED and LCD displays, a universal matrix keypad, an RS232 terminal and a whole library of switches, pots, lamp
