Pep8 intro #2 - assembly language

00:04:43
https://www.youtube.com/watch?v=QtFgBe18oPI

概要

TLDRThis tutorial demonstrates how to use the Pep/8 simulator for entering, assembling, and running an Assembly Language program. The process starts by configuring the simulator's view to show the source code area, architecture controls, and memory dump. The assembly source code is entered into the designated window, and then the program is assembled to convert the code into machine language. Before assembling, it's essential to clear memory to avoid interference from previous data. The converted machine code is loaded into memory, and decimal input values can be provided for the program to process. The tutorial illustrates step-by-step debugging, showing how instructions are fetched and executed, with intermediary results stored in the accumulator. The entire process is case-sensitive and demonstrates the workings of assembly language computation, specifically performing arithmetic operations, with the program outputting a result of 60 by summing input values. This tutorial offers practical guidance for understanding the machine-level processing of assembly instructions using the Pep/8 simulator.

収穫

  • 🔧 Learn to use Pep/8 simulator for Assembly Language.
  • 📜 Enter source code in the source code window.
  • 💡 Always clear memory before assembly.
  • 🔄 Assemble code to convert to machine language.
  • 🔍 Debug by single stepping through instructions.
  • 🔢 Use the accumulator register for storing results.
  • 📝 Be mindful of case sensitivity in code.
  • 📊 Input values are processed from input window.
  • 🖥️ View changes in memory after loading program.
  • ➕ Example demonstrates arithmetic operations.
  • 🚀 Final output of example program is 60.
  • 🔂 Simulator helps understand assembly computation.

タイムライン

  • 00:00:00 - 00:04:43

    The tutorial covers using the pep8 simulator for entering and converting Assembly Language code to machine language, and then running it. The process starts with configuring the simulator view to display the source code, architecture, and memory dump areas. Assembly code is entered in the 'source code' area, unlike machine code which is entered in 'object code'. An example from a book is used to guide the input process, emphasizing case sensitivity in the code. Upon entering the assembly program, the tutorial moves to converting it into machine language and highlights the importance of clearing memory before assembly. The software assembles the code, displaying the corresponding machine code in the simulator. It is then loaded into memory, followed by the execution phase which allows adding inputs in decimal form. The process includes debugging and single-stepping through instructions to observe the program counter and accumulator registers to track operations, demonstrating arithmetic functions like addition within the program.

マインドマップ

Mind Map

よくある質問

  • What tool is being used in the tutorial?

    The tutorial uses the Pep/8 simulator.

  • What is the first step in using the Pep8 simulator?

    The first step is to set the view to show the source code area, architecture area, and the memory dump.

  • Where should the Assembly Language source code be entered?

    The source code should be entered in the 'Source Code' window.

  • What happens after assembling the program?

    After assembling, the program is converted to machine language, and you can see the corresponding object code.

  • Why is it important to clear memory before assembling?

    Clearing memory ensures that previous data does not interfere with the new program.

  • How does the simulator process input values?

    The simulator grabs input values from the input window as needed by the program.

  • What is the purpose of the accumulator register?

    The accumulator register (A register) is used for storing results of operations like addition or subtraction.

  • What must you be cautious about when entering the program?

    Be cautious of case sensitivity in Assembly Language commands in the simulator.

  • What is the output of the demonstrated program?

    The output of the program was 60, demonstrating addition of input values.

  • What does single stepping through the program show?

    Single stepping shows how the program counter fetches instructions and processes them sequentially.

ビデオをもっと見る

AIを活用したYouTubeの無料動画要約に即アクセス！
字幕
en
オートスクロール:
  • 00:00:01
    all right this is part two of our
  • 00:00:02
    tutorial in this case we're going to be
  • 00:00:04
    using the pep8 simulator to load to
  • 00:00:08
    enter in Assembly Language an assembly
  • 00:00:09
    language
  • 00:00:10
    program to then convert it into machine
  • 00:00:13
    language and then to run it it's very
  • 00:00:15
    similar couple extra steps but uh very
  • 00:00:18
    similar to what we did with the machine
  • 00:00:20
    language program so the first thing
  • 00:00:22
    we're going to do is what I mentioned
  • 00:00:23
    before is go up and go ahead and put
  • 00:00:24
    this in three view so that we have I
  • 00:00:27
    left click here so that we have the
  • 00:00:29
    source code area
  • 00:00:30
    the architecture area showing the
  • 00:00:31
    registers as well as the memory dump so
  • 00:00:34
    unlike with machine code object code
  • 00:00:38
    we're going to be entering our source
  • 00:00:39
    code in the source code window here so
  • 00:00:41
    previously we entered the machine
  • 00:00:43
    language code down here in object code
  • 00:00:45
    so now what we're going to do is we're
  • 00:00:46
    going to enter it in the source code
  • 00:00:48
    area an example that we're going to work
  • 00:00:50
    with is the example from page 171 in the
  • 00:00:52
    book there's a an assembly language
  • 00:00:54
    program there and so I'm going to enter
  • 00:00:56
    that program in this upper window so
  • 00:01:00
    [Music]
  • 00:01:02
    V main it does send does seem to be a
  • 00:01:06
    bit sensitive to case so go ahead and
  • 00:01:08
    try to maintain the case if it's a large
  • 00:01:11
    uppercase BR put a uppercase BR things
  • 00:01:13
    like that that means Branch obviously so
  • 00:01:15
    I'm going to continue to enter this
  • 00:01:16
    program into the source code window and
  • 00:01:19
    I'll be right back all right as you can
  • 00:01:20
    see I've entered the example from page
  • 00:01:23
    171 into the source code window here so
  • 00:01:27
    you can scroll down and see the whole
  • 00:01:28
    program
  • 00:01:30
    and
  • 00:01:31
    uh anyway I won't talk about the
  • 00:01:33
    different language instructions or
  • 00:01:34
    assembler directives that are here but
  • 00:01:36
    you can see that we're allocating some
  • 00:01:38
    memory here and then we have our actual
  • 00:01:40
    Assembly Language instructions down here
  • 00:01:42
    all right so now with Assembly Language
  • 00:01:44
    programs we have to convert it into
  • 00:01:46
    machine language before the computer can
  • 00:01:48
    actually run it and so and so in order
  • 00:01:50
    to do that again I always stress going
  • 00:01:52
    up to system clear memory so the first
  • 00:01:56
    thing we want to do is go to build and
  • 00:01:58
    we need to assemble this program okay we
  • 00:02:00
    need to assemble the program so left
  • 00:02:02
    clicked on assemble and notice what's
  • 00:02:05
    happened now so now we have our source
  • 00:02:07
    code here in Assembly Language now we
  • 00:02:10
    have the object code the machine
  • 00:02:11
    language that actually corresponds to
  • 00:02:14
    this source code up here and um so we've
  • 00:02:19
    now assembled it converted it from
  • 00:02:22
    Assembly Language into machine code and
  • 00:02:24
    so now just like we would do with a
  • 00:02:26
    regular machine language program an
  • 00:02:29
    object code program
  • 00:02:30
    we want to load that program notice
  • 00:02:32
    initially we have nothing in memory so
  • 00:02:34
    now we want to load this program just
  • 00:02:36
    like before with the machine language
  • 00:02:39
    code that we did before load it and
  • 00:02:41
    notice now the contents here have been
  • 00:02:45
    copied into memory just as we saw in the
  • 00:02:47
    first tutorial and so now it's exactly
  • 00:02:50
    the same kind of thing that happened
  • 00:02:51
    last time in this case we want to have
  • 00:02:53
    some inputs so this is a good example of
  • 00:02:55
    some inputs this program has some uh
  • 00:02:58
    deci decimal input values so let's just
  • 00:03:01
    throw in a couple values here just to
  • 00:03:03
    give the program something to work with
  • 00:03:05
    and notice that I did not put any commas
  • 00:03:07
    or anything between them so um what the
  • 00:03:09
    program will do is it will grab values
  • 00:03:11
    from this window here the input window
  • 00:03:13
    as it needs them and so now I've loaded
  • 00:03:17
    it I've put values for batch IO inputs
  • 00:03:20
    here so now again just like before I'm
  • 00:03:23
    going to go to start debugging
  • 00:03:26
    object and I'm going to single step
  • 00:03:28
    through it and just like before for what
  • 00:03:30
    we're going to see is that the um the
  • 00:03:33
    program is the program counter is
  • 00:03:35
    pointing at the next instruction to be
  • 00:03:36
    fetched so those three bytes are in blue
  • 00:03:39
    the operand and instruction specifier
  • 00:03:41
    are shown here in these registers here
  • 00:03:44
    and the other thing that I didn't point
  • 00:03:45
    out previously is that here's the
  • 00:03:48
    accumulator register the a register
  • 00:03:50
    which is where we're storing our results
  • 00:03:53
    and so what we want to do is notice that
  • 00:03:54
    the um is that some of these programs
  • 00:03:56
    we're going to want to pay attention to
  • 00:03:58
    if it's doing addition subtraction or
  • 00:04:00
    whatever that um what's going on in the
  • 00:04:02
    accumulators where that's going to be
  • 00:04:03
    happening and so notice that the
  • 00:04:05
    accumulator is showing the value here in
  • 00:04:07
    HEX of what's in there the contents and
  • 00:04:09
    then to the right is the decimal value
  • 00:04:11
    associated with the accumulator anyway
  • 00:04:13
    so we can just keep single stepping and
  • 00:04:16
    um until we hit the
  • 00:04:19
    stop and then we hit the stop
  • 00:04:22
    instruction and uh the program completes
  • 00:04:25
    with an output of 60 and so in this case
  • 00:04:27
    what did it do must have added uh 10 +
  • 00:04:29
    20 is 30 + 30 is 60 and didn't use that
  • 00:04:32
    last input value but basically the idea
  • 00:04:35
    here was just to demonstrate how this
  • 00:04:36
    particular program actually how the
  • 00:04:39
    simulator works with assem language code
  • 00:04:42
    [Music]
タグ
  • Pep/8 simulator
  • Assembly Language
  • machine code
  • program assembly
  • memory management
  • accumulator register
  • program input
  • debugging
  • instruction execution
  • program output