johnny - documentation

Simulation of a von neumann arcitecture

The core of this version is at https://github.com/Laubersheini/johnny to be found. This version contains a lot additional and useful features besides bugfixes.

johnny - modifications

johnny changes

This edited version can be viewed at https://tobisma.github.io/johnny

• implement a button to insert a row above the current selection
• delete selected row
• when selecting an address row, make the value available to edit directly in the input field
• focus the input on selection of an address
• intelligent number reading when editing RAM values (e. g. 1.3 is understood as 01.003 which would be TAKE 003)
• fixing some issues when resizing the page
• made electron packagable
• implemented shortcuts for menu bar and ram moving
• implemented VIM style shortcuts for buttons
• remember execution speed
• only allow writing numbers in input fields
• remember configured execution speed
• more intuitive scroll behaviour
• settings
  • turn on/off correcting RAM macro commands on insert/delete row
  • configure how many lines if available should be above/below the selection while scrolling using arrows keys or j k
• undo/redo on Ctrl Z and Ctrl Y  
• setting to configure how many actions are remembered
• prompt when saving RAM or micro code in a file
• documentation of the micro code numbers in the downloadable file
• editing already recorded micro instructions
• renaming macro codes in the microcode registers
• checking for name collision
• no multiple additions to the macro code selection
• better numbering system for where to start the new macro code

overview about the numbers used in a *.mc file

Made by Sagalim and Isabell05

how does single micro code instruction editing work?

To get the menu for editing you need to make a click on the entry in the micro code table. Then, an prompt pops up asking for a number or a button. The numbers are the micro code instrcution numbers listed in the table above. When clicking on the input field a list with possible optinos will show.

The buttons are text input. They are parsed by checking the start of the input and the end. You can either just type out the full button like db --> ram or continue reading to understand how to shorten your buttons. The numbers are the shortest way, but also the most complicated. As always, there are exceptions. Those are listed at the end.

Buttons are built using the following operators and destinations:

Destinations

Operators

Operators are always used after an Destination

how to build your buttons

from destination to destination

just type the first destination (the starting point) followed by the second destination. For example, dbram would translate to db --> ram or insab would translate to ins --> ab. As mentioned in the beginning typing db --> ram works fine as well, because it still starts with db and ends with ram.

destination prepended to an operator

Examples: acc-, pc+, mc0
acc- and pc+ just mean acc++ and pc++. It is just an character shorter
mc0 is a bit more complicated but button inputs ending on 0 mean to reset the destination. So, mc0 refers to mc:=0 and acc0 would be acc:=0.

The exceptions

• ^ prepended to a code block signals that the input needs to start with this code block
• $ prepended to a code block signals that the input needs to end on that code block

---

For example ^'ram' $'db' describes that the input needs to start with ram and needs to end with db. This input corresponds to the button ram --> db

shortcuts

basic shortcuts for menu and RAM

Actions on RAM which are possible from micro code, as well (e. g. save) are with perssing ⇧ Shift additionally.

shortcuts for buttons like ram --> db

Those shortcuts are in VIM style meaning you need to enter command mode first by pressing :(VIM keybinding) or V (added by this website). Afterwards you type the commmand from the list below. Then press ⏎ Enter to emulate pressing the button. While in command mode you can press Esc or ^ Ctrl C to leave command mode. While in command mode all basic shortcuts above are disabled. The visual feedback is in command mode in the bottom left corner.

List of commands in command mode

List of commands for the control unit

NOTE: they are also working when the control unit is not visible

List of commands for menu bar

How to remember them?

They are made of "operators" (and similar to the buttons read when editing micro instructions):

By putting them together buttons like ram --> db are represented as rd with the meaning from r(ram) to d(data bus).

Adding + or - causes counting buttons to be triggered. For example p+ means to add to the program counter. An alias would be p++. Just for the case someone types two +. In a context like a+ the a stands for Accumulator instead of Address Bus because there are no counting buttons for the address bus.

browser compatibility

I recommend to use Firefox (continue reading for the reason).
This website works on Firefox and chromium based browsers (Edge, Chrome, ...). Not listed browsers have not been tested which does not mean they are not compatible.

NOTE: If the dataset gets larger the time to update the RAM rows becomes longer. But it has been fixed, so that chromium base browser only need ~500ms instead of 3.5sec

package using electron

1. Clone the repository locally and move into the folder
2. Run npm install
3. Make sure npx is globally accessable, otherwise edit either package.json to match your requirements or install npx
4. For Windows run npm run package-win and for linux run npm run package-linux. This will create a folder in executables for the windows or linux executable version. Beware, that it overwrites this folder, should this folder already exist and it is always for the x64 arcitecture. To change that behaviour, edit the package.json file
5. Go into the generated folder and run Johnny.exe to start the app