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Text File | 1986-02-21 | 15.3 KB | 352 lines

SECTION PAGE # INTRODUCTION Purpose of this software .................. 1 Current Capability ...................... 1 Future Enhancements ..................... 2 Support for Abel ...................... 2 Support for Cupl ...................... 2 Reduction of Boolean Equations ........ 2 GETTING STARTED Hardware Requirement ...................... 3 Minimum Required System ................. 3 Recomended Hardware ..................... 3 Main Menu Commands ........................ 4 Naming the pins ......................... 4 Entering the signal list order .......... 4 Drawing the signals on the screen ....... 4 Creating the PALasm 2 formated file ..... 5 How to exit and save your work .......... 6 How to exit without saving your work .... 6 SAMPLE DESIGNS 4 bit counter ............................. with reset .............................. with set, reset, and load ............... 8 bit ring counter ........................ with reset .............................. with reset and hold ..................... ADVANCED FEATURES More than one state machine in a PAL ...... Extended simulation capability ............ Designing a continuous counter ............ LIMITATIONS *** CAUTION *** ........................... WHO TO CONTACT WITH PROBLEMS ................ A. INTRODUCTION 1. Purpose of this software a) Current Capability The TiDE program is very nearly a finished product. In the near future there will be a few minor additions to the software which will be discussed in the next paragraph. Aside from these additions I will take sugestions from users of the software on what they would like to see added or changed. In the present revision [ver 2.16] only registered outputs are supported. This will be changed in ver 2.17 and latter versions. The TiDE software will allow a design engineer to enter a minimal amount of information about the actual device to be used and then enter a description of what the state machine should do by drawing the timing diagram on the screen of the PC or PC clone. b) Future Additions 1) Support for Abel In the near future TiDE will ask you if you will be using MMI's PALasm 2 or Data I/O's ABLE software. It will then generate the proper file for use with your software. 2) Support for Cupl Due to the fact that I have not seen as many customers using the Assisted Technology CUPL software I will be waiting to see the number of requests that I get for this feature. If enough people want it I will do it. 3) Reduction of Boolean Equations I had intended to include a boolean reduction program for use with PALasm 2 but I now feel that it would be better to release a working version of the program and then add the reduction routine in a future release. B. GETTING STARTED 1. Hardware Requirement a) Minimum Required System The minimum system that this software has been tested on was a DATA GENERAL ONE laptop computer with 256 K of memory. This system is an MS Dos machine with a few exceptions. I feel that if it runs on this machine it should run on any MS Dos computer. If you find an MS Dos machine that this will not run on please contact me with the details. Due to the method used for drawing the wave forms you do not need to have any graphics capability at all. The program is small enough to only require a single floppy disk to hold both the program and the files created by the program. With these limited requirements it should be possible to run TiDE on allmost any MS Dos computer. b) Recomended Hardware There is only one piece of hardware that would make a nice addition and that is an IBM graphics printer. The Epson printers and their clones will not work for screen dumps of the timing diagram without the use of special software such as Print Works by SoftStyle. The reason for this is that the graphics on the screen are only the extended character set of the IBM PC and are not really graphics at all. On an Epson or equivalent the graphics characters are not there and instead you will get italics characters. This is only a limitation if you wish to get a hardcopy of the screen while in the drawing mode. 2. Main Menu Commands a) Naming the pins - F1 This is the first option on the main menu and it is used to enter the mneumonics that you wish to assign to the inputs and outputs of the device to be designed. To invoke this Press the F1 key while the main menu is desplayed. This is the first thing that must be done on any new design. b) Entering the signal list order - F2 This option does not need to be used unless you wish to have the signals shown in an order other than the pin number order. When you use this option you have the ability to have the same signal displayed as many times as you wish. The only warning is that a signal that is showing in two or more places on the screen should not be edited. You will get very strange results if you try to do this. Even with this precaution you may wish to display the same signal more than once to allow you to compare the timing of this signal to another. c) Drawing the signals on the screen - F3 This is the fun part. Once you have entered the pin names you may begin to draw the signals by using this option. A menu of the available commands is located at the bottom of the screen. This menu lists all of the keys that may be used to enter data, edit signals, or control the screen. The first part that we will discuss is the method for entering the data. The valid input keys for this are the "X", "H", and the "L" keys. Upper or lower case will work. The meaning of the keys are: X : don't care - the signal is undefined at this point. H : high - on input signal - pin will be high during the next rising edge of the clock. on output signal - this signal is to go high after the next rising edge of the clock if the previous columns conditions are met. L : low - same as for H except defines the low condition. The character entered will be displayed directly above the cursor after which the cursor will advance one position. The four arrow keys will all move the cursor in the indicated direction. The cursor may not be moved off of the screen nor will it scroll the screen when it hits the top or bottom. If you wish to view the next five signals press the pgdn key on the cursor control keypad. To view the previous five signals use the pgup key. Due to the fact that there are seven signals displayed on the screen there will always be a two signal overlap for continuity. The last of the control keys are the ins and del keys again located on the cursor control keypad. These keys will allow you to insert a spot into a signal which can then be changed to the proper value. The cursor should be placed under the first location that is to be moved to the right to make room for the new value. The del key will delete the value directly above the cursor and move everything to the right of the cursor left to fill the hole. The use of these two keys will help when you wish to make a small change after entering a long signal so as not to have to enter the entire signal again. d) Creating the PALasm 2 formated file - F4 After you have entered the timing diagram you are ready to produce the text file which will contain the heading, equations and the simulation in a PALasm 2 format. If you follow all the steps carefully in your design you should not have to use an editor on the file at all. It is usually possible to generate a file which is complete and ready to be assembled into the fuse pattern for your part. When this section starts it will ask you for a file name. At this point you should enter the name for the PALasm 2 file. Standard convention dictates that the extension to the file name should be ".PDS", this stands for Pal Design Specification. Care should be taken here not to enter a filename that is already being used, at present no checking is done to insure that a file is not overwritten when the new file is created. This is a feature that will be added to a future version. After you have entered the filename you will be asked several questions. If you are familiar with PALasm 2 you will recognize that each of these questions is for the heading of the file. If you are just testing a portion of your design and this will not be the final version of your design you may just press the ENTER key and leave the heading blank. The exception to this is the part type, if you do not enter a part type the software will declare the part as a PALXXXX in the text file. At this point the file will not work with palasm and you will have to use an editor to change the part type to a valid one. This can be used to your advantage if you wish to get the equations and then go back to decide which Pal you wish to use. The last question will ask you if you are using a part which has the capability of programmable output polarity. If you answer this question yes the software will determine if an output should be written active low or active high based on which will require the least number of product terms. If you are not using a part with programmable polarity all equations will be written active low. An example of a part with programmable output polarity is the PAL16P8 vs. the PAL16L8. The P in the part number designates that the part has programmable polarity. Many of the new parts being done by MMI have the added feature of programmable polarity. e) How to exit to Dos and save your work - F5 When you have finished entering information or if you are interrupted you may save your work and continue it at a latter time. This will save all pin names and signal values that have been entered up to this point. This will also allow you to come back into the screen editor and change the timing diagram if you find a problem in the PAL at a latter date. f) How to exit to Dos without saving your work -F6 I hope that you will not need this option but if you do here it is. If you make a major mistake while editing your design file and you decide that you would like to lose the changes that have been made since the last save you may do so by using this key. A check is made to insure that you really want to do this as there is no turning back once it is done. C. SAMPLE DESIGNS 1. 4 bit counter a) with reset b) with set, reset, and load 2. 8 bit ring counter a) with reset b) with reset and hold D. ADVANCED FEATURES 1. More than one state machine in a PAL Due to the way that this software generates the equations to implement your design it is possible to define multiple independent state machines in the same device. In order to do this all you will have to do is insure that the seperate sections are not drawn under each other. This means that at least one column of nothing but don't cares must seperate the sections. You can use this method to implement several different sections in the same device. 2. Extended simulation capability When the simulation section of the output file is being generated it works from the timing diagram. The only signal lines that it looks at are the input signals and the control signals such as output enable. By extending one of the input signals such as a output enable type simulation will continue. 3. Designing a continuous counter In order to make a state machine that will loop back on itself you will need to show the starting point for the loop as the last column of the design. For examples of this and other special features look at the sample files on this disk. Files with an extension of ".SIG" are design examples that you can use to experiment with. E. LIMITATIONS 1. *** CAUTION *** This section will be used to list bugs that have been found and reported. I will try to keep this section of the manual current. Since this is the first official release of the program I do not have any reported bugs as yet. F. Who to contact with problems If you have a problem with the operation of this software or if you decide that a feature needs to be added I have a computer bulletin board which you may use to leave me a comment. The phone # for the board is (513) 866-5157. This board will also contain the latest version of this software along with the manual, as well as having other utility programs to help you in designing with MMI Pal devices. G. Credits Author : Bill Hollon Field Applications Engineer Monolithic Memories Inc. 261 Trumpet Drive Dayton, Ohio 45449 Concept and Ideas : Mike Wier Regional Sales Manager Monolithic Memories Inc. Anyone who makes a contribution of a signifigant idea will be added to this list. So send in any and all ideas for improvement. Thanks; William R. Hollon