Uploaded September 2020 | Updated September 2026, 2 weeks ago

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In this episode, we're going to implement 2 new features in the assembly language and assembler of the machine. The first is the ability to specify named, arbitrary data inline with the assembly code. And the second is the ability to specify named constants - whose values can be used meaningfully in the assembly code.



00:00 - Intro
01:23 - Parsing data directives
04:54 - Parsing constant directives
05:33 - Updating the main parser
06:03 - Writing a test program in assembly
07:03 - Refactoring the assembler
08:02 - Extracting constant and semantics in the assembler
08:58 - Encoding data blocks in the generated binary
10:17 - Testing the new assembler features



 =[ ℹ About ℹ ]=


This series is all about building a powerful virtual machine in JavaScript with the following features:

- A flexible, extensible, register-based virtual machine
- Support for signed, unsigned and floating point operations
- A call stack
- Interrupt capabilities
- Ability to do memory mapping for IO
- An assembly language with macro and module support
- A higher level, C like language. We'll use and expand the library from the parser combinators from scratch series
- And finally, to be able to take the whole thing into the browser and extend it to create a sort of fantasy console - an emulator for a machine that never existed


=[ 🔗 Links 🔗 ]=



- 💌 Updates to your inbox: tinyletter.com/lowleveljavascript
- ⭐️ Patreon: patreon.com/lowleveljavascript



- Assembly language tour (16-Bit VM ep 7) : youtu.be/ai63l4OUxSs
- Data directives: en.wikipedia.org/wiki/Assembly_language#Data_directives



- Series Playlist: youtube.com/playlist?list=PLP29wDx6QmW5DdwpdwHCRJsEubS5NrQ9b&playnext=1&index=1
- Github Repo: github.com/LowLevelJavaScript/16-Bit-Virtual-Machine