1 00:00:01,565 --> 00:00:11,165 Hi, I'm Nick Chen, one of the teaching assistants for Rob Rutenbar's VLSI CAD 2 00:00:11,165 --> 00:00:16,514 Logic to Layout course. This is the first tutorial in a series of 3 00:00:16,514 --> 00:00:21,079 video tutorials introducing you to several tools that you can use in this class. 4 00:00:21,080 --> 00:00:24,590 The first tool that we will introduce is KBDD. 5 00:00:24,590 --> 00:00:30,938 Kbdd is a BDD calculator done by Professor Randy Bryant's group at Carnegie Mellon 6 00:00:30,938 --> 00:00:35,337 University. This tutorial has an accompanying document 7 00:00:35,337 --> 00:00:39,954 that you can refer to. This document will be available on the 8 00:00:39,954 --> 00:00:43,998 class website. The example that we will be going through 9 00:00:43,998 --> 00:00:47,852 today is the network repair example from this document. 10 00:00:47,852 --> 00:00:51,821 It's displayed here on the right hand side of the screen. 11 00:00:51,821 --> 00:00:57,397 The purpose of this video tutorial is not to explain everything in that document, 12 00:00:57,397 --> 00:01:02,692 but to show you how you can interface with it to, through the web interface. 13 00:01:02,692 --> 00:01:08,934 I've copied and pasted the KBDD com, commands from the documents to this text 14 00:01:08,934 --> 00:01:12,111 file. As you can see I removed all the KBDD 15 00:01:12,111 --> 00:01:15,578 prompts and just entered the commands as is. 16 00:01:15,578 --> 00:01:21,406 You can enter the commands in your favorite text editor, save it and upload 17 00:01:21,406 --> 00:01:26,090 it to the website. Here's how you navigate to the tools 18 00:01:26,090 --> 00:01:28,756 section. I'm showing you our class website. 19 00:01:28,756 --> 00:01:33,724 On the left-hand side of the screen you can see the Programming Assignments tab. 20 00:01:33,724 --> 00:01:37,642 And we click on it, and it brings me to this Programming Assignments page. 21 00:01:37,642 --> 00:01:43,162 Under the Tools section, you can find the first tool that we've introduced, KBDD. 22 00:01:43,162 --> 00:01:47,161 If you wish you can actually click, and see the instructions that we have for this 23 00:01:47,161 --> 00:01:50,726 particular assignment. I'm not going to click on it now, but you 24 00:01:50,726 --> 00:01:53,817 can do it, when you try the tool out for yourself. 25 00:01:53,818 --> 00:01:57,448 This programming assignment page will also be populated with more programming 26 00:01:57,448 --> 00:01:59,927 assignments for the course as the course progresses. 27 00:01:59,928 --> 00:02:04,710 What I'm going to do now is show you how to actually submit the text file that we 28 00:02:04,710 --> 00:02:10,633 have just saved. You select the submit button here, choose 29 00:02:10,633 --> 00:02:17,931 Output Submission and navigate to the file that you just saved. 30 00:02:17,931 --> 00:02:25,705 Click submit and you'll be presented with a screen that says your submission has 31 00:02:25,705 --> 00:02:32,925 been accepted and will be graded shortly. Go back to the Programming Assignments 32 00:02:32,925 --> 00:02:39,822 page. After a few moments, if you click View, 33 00:02:39,822 --> 00:02:48,509 you'll be able to see your results. Here is our results. 34 00:02:49,790 --> 00:02:53,393 You can see a submission time and you can see a raw score. 35 00:02:53,394 --> 00:02:57,950 As mentioned before in the announcement, the raw score does not contribute towards 36 00:02:57,950 --> 00:03:00,922 your final grade for this class. Here's the feedback. 37 00:03:00,922 --> 00:03:07,978 One thing that you may have noticed here is that the first two lines where not 38 00:03:07,978 --> 00:03:14,955 entered in your, in your text file. What we have here is an additional command 39 00:03:14,955 --> 00:03:19,439 that we alternately enter on our site. Its purpose is to prevent canon scripts 40 00:03:19,439 --> 00:03:21,940 from consuming too much memory on our back end. 41 00:03:21,940 --> 00:03:27,267 Basically, it tells and limits KBDD to how much memory it can consume. 42 00:03:27,268 --> 00:03:30,790 You don't have to worry about this since all the assignments for this class are 43 00:03:30,790 --> 00:03:33,000 designed to fit within the memory constraints. 44 00:03:33,000 --> 00:03:39,176 Here, I'm going to show the results of running your commands and the results from 45 00:03:39,176 --> 00:03:43,287 the tu, tutorial. As you can see, both of them match. 46 00:03:43,288 --> 00:03:48,532 Here is for the output from evaluating eval cout a and b and here's the 47 00:03:48,532 --> 00:03:54,094 accompanying output as well. You can verify this on your own as you try 48 00:03:54,094 --> 00:03:57,509 out the two. Now consider what happens if I 49 00:03:57,509 --> 00:04:03,802 accidentally enter something wrongly. So for instance, on line five here, 50 00:04:03,802 --> 00:04:08,014 instead of the variable cin, I'm going to put cind. 51 00:04:08,014 --> 00:04:11,649 Now I go back to the Programming Assignments page, and I submit that file. 52 00:04:11,649 --> 00:04:26,167 (Clicking) Sometimes the results are not immediately available, and you will see 53 00:04:26,167 --> 00:04:35,808 here that you have nothing here. Just wait patiently and refresh the page. 54 00:04:35,808 --> 00:04:41,220 Here you go. We have the same output as before except 55 00:04:41,220 --> 00:04:47,612 now on this particular line KBDD informs us that it's not able to find the variable 56 00:04:47,612 --> 00:04:50,518 of cind. As you can see KBDDs quite robust to the 57 00:04:50,518 --> 00:04:54,658 inputs that you can give it. However, in the event that the two 58 00:04:54,658 --> 00:05:00,862 actually does crash from some command you give it, you'll be able to see the KBDD 59 00:05:00,862 --> 00:05:04,180 standard error. You can report this to us and we can 60 00:05:04,180 --> 00:05:07,170 investigate what happened, and there you have it. 61 00:05:07,170 --> 00:05:11,643 A very short introduction of how you can use the KBDD tool, through the class 62 00:05:11,643 --> 00:05:14,447 website. Please let us know if you have any 63 00:05:14,447 --> 00:05:17,670 questions through the discussion forms on our class website. 64 00:05:17,670 --> 00:05:20,153 Thank you.