kenh@tekcbi.UUCP (Ken Hillen) (03/05/85)
After playing with the Rune Software Electronic Pad 512 demo package for several days I have the following observations: 1. The Electronic Pad provides you with 9 'pages' about the size of a MacPaint window into which to enter your schematic. You do not get a large scrollable window to work in. You must make connections between these pages. 2. The connections between the pages are made via labeled 'Terminals' which must be on each page that uses the signal, and the labels must match (there is no way to copy a label so you must remember the label name when you add it to a new page). The terminals and thier labels take up a lot of scarce circuit area. 3. The circuit elements and their labels are large enough that putting more than about 12 elements per page could be a real challange. The documentation claims that circuits with up to 160 components can be simulated. 4. Each circuit element has a label and a propagation delay associated with it. In the case of flip-flops it appears that all prop times are equal, and I have found no information on set-up and hold times of the flip-flops. 5. The circuit elements available are: AND, OR, NAND, NOR, XOR, XNOR, NOT, D flipflop, JK flipflop, Terminal (used to connect signals to other pages), Input (signal source with up to 40 transitions specifiable), Output and Probe (to gather data to display when doing a timing simulation). There is no tri-state capability in these components, and no method of creating new symbols (all of the gates are 2 input--I'd like some with more inputs!). 6. Once a circuit element is placed on the page, it is fixed. To move it you must DELETE it and then recreate it. There is no click-drag-release or even cut & paste available. 7. Logical connections are made between devices by selecting clicking on an output and an input. A line is then automatically drawn between the two nodes. The autorouting algorithm is very good at drawing parallel lines on top of each other, so it becomes very hard to tell what is connected to what. 8. A 'macro' capability allows you to create a one-page ciruit that can be included in other designs. The macro takes up one page of the design it is add to (instead of being a nice little 'black box' with terminals to connect to). All connections to the macro are via the above mentioned terminals. Note that if the macro is small other components can be added to the page after the macro is put on, but a macro must be the first thing on a page and is put there in exactly the same form and position as when it was created with the macro editor. 9. The circuit simulation capabilities seem to be OK. Comparing its output against a (very accurate) mainframe based program did uncover some minor differences. The simulation ran comfortably fast on a circuit of about 25 components. It also appeared to handle asynchronous events with no trouble. The documentation claims 85% simulation accuracy. 10. The simulation allows you to specify a start time and a sample time. The output displays 6 samples starting at the specified time. Up to 12 signals can be displayed. The 12 signals are selected by connecting 'probes' to circuit nodes. 11. The only way to print any output (either schematic or simulation) is via the command-shift-4 to printer or command-shift-3 to a macpaint document. In my opinion the package is a good demonstation of the type of SW that can be witten for the Mac. If you can live with the user interface, the package is probably OK. I am hoping that the user interface will be made more Mac-like, and that the macro and printing capabilities are enhanced. The simulation seems to be up to snuff for a $600 package. The wisest thing to do is get the demo package and play with it to determine if it meets your needs. The opinions expressed here are mine and do not necessarily reflect the views of my employer or anyone else (I'm very opinionated you know). Ken Hillen tektronix!tekcbi!kenh