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DeZog - The Z80 Debugger
The objective of this project is to provide a development environment for Z80 assembler programs that offers similar features to those found in high-level programming languages, such as Eclipse, Visual Studio, or XCode.
This includes functionalities like
DeZog facilitates the debugging of Z80 assembler programs using Visual Studio Code (vscode) as the development environment. This tool can be used to build programs, step through sources, use labels, watches, memory views, and other useful features. Additionally, it can be used to reverse engineer old Z80 programs, such as ZX Spectrum or MAME arcade games, by debugging and creating commented list files of the program.
DeZog needs a "Remote" to execute the Z80 binaries. You can either use the built-in Z80/ZX simulator or connect to ZEsarUX, CSpect or MAME via a socket connection for more advanced projects.
Note: DeZog itself does not include any support for building from assembler sources. For this you need a build task and an assembler. For an example look here: https://github.com/maziac/z80-sample-program
In order to use DeZog you need at least vscode (Linux, macOS or Windows).
If you are writing pure Z80 programs or simple ZX Spectrum 48K programs this might already be sufficient as you can use the internal Z80 Simulator.
For more demanding projects you have the choice to install a real emulator.
These are the options:
The different DeZog/emulator configurations have different advantages. But which one you choose mainly depends on your personal preference. The table here shows a comparison of the features.
If you own a ZX Next you also have the option to debug your SW directly on the Next.
To use DeZog, at least vscode is required (available for Linux, macOS, or Windows).
For pure Z80 programs or simple ZX Spectrum 48K programs, the internal Z80 Simulator within vscode may be sufficient.
For more demanding projects, you can choose to install a real emulator. The following are available options:
CSpect emulator (interoperable with version 18.104.22.168) ZEsarUX emulator (interoperable with version 10.1, but not with 10.2) MAME (interoperable with version 0.242) Different DeZog/emulator configurations have their own unique advantages, but the choice mainly depends on personal preference. A comparison of features can be found in the table available in the documentation.
If you own a ZX Next, you have the option to directly debug your software on the Next, too.
In Visual Studio Code simply install "DeZog" (maziac.dezog) from the Marketplace.
There are a few other extensions that are not required to work with DeZog but may help:
All can be installed directly inside vscode from the market place.
To use DeZog in Visual Studio Code, simply install the "DeZog" extension (maziac.dezog) from the Marketplace. Although not required, there are several other helpful extensions available, including:
All of these extensions can be easily installed directly from the Visual Studio Code Marketplace.
Please refer to the 'Usage of DeZog' documentation.
You can also access the documentation from within vscode/DeZog. Enter "dezog: Show the DeZog Help page" in the command palette (F1 key) or reveal the "DeZog Help" from the debugging sidebar.
If you would like to help extending the DeZog functionality in one of the following areas you are very welcome:
You can create a pull request so I can add your sources to the official release. Most probably I will first move them to a new feature branch for testing. Please note that all your contributions/sources should be under MIT license.
If you would like to contact me beforehand you can create a new issue in github and we can discuss.
DeZog is licensed under the MIT license.
The source code is available on github.
DeZog also includes a Z80/48k ZX Spectrum simulator. For this the original 48/128k ROM code is included and here is the copyright notice: "Amstrad have kindly given their permission for the redistribution of their copyrighted material but retain that copyright". See Amstrad ROM permissions.
Furthermore DeZog includes slightly modified sources of the Z80.js simulator. It was taken from https://bitbucket.org/DrGoldfire/z80.js/src/master/ which is MIT licensed. Many thanks to Molly Howell.
For the "What's New" feature the vscode-whats-new project from Alessandro Fragnani aka alefragni has been incorporated. The project is MIT licensed.
For the other included SW see the 'dependencies' section in package.json
I would like to express my gratitude to the following individuals for their invaluable support:
Please note that the tutorials listed here are normally not updated when a new DeZog version arrives. Especially for changes in the 'launch.json' it might happen that some properties (names) have changed/removed/added.
If you are writing a tutorial please let me know, I'm happy to list it here. Any contributions are very welcome.
The tutorials that I'm aware of are listed here by date.
A Man in his Techno Shed
Date: Apr-2022, DeZog 2.7, ZX Next
The most recent and only tutorialtutorial for DeZog 2.x, by A MAN IN HIS TECHNO SHED. It shows debugging with a ZX Next and DeZog.
Date: Sep-2020, DeZog 1.4, CSpect
A great tutorial by Patricia Curtis describing the setup with sjasmplus, CSpect and DeZog.
Retro Coder TV
Date: Sep-2020, DeZog 1.4, Internal Z80 Simulator, ZEsarUX, CSpect
A quite lengthy tutorial. But as a YouTube video it shows a 'live' DeZog setup. By Retro Coder TV.
L BREAK into program, 0:1
Date: Aug-2020, DeZog 1.4 (with a few updates for 2.0), ZEsarUX
And here is another shorter tutorial by Dean Belfield (L BREAK into program, 0:1).
Date: May-2020, DeZog v1.2, CSpect
An excellent tutorial by Daren May which shows how to setup DeZog with CSpect on Windows. Although it was made for Windows you can easily apply it to macOS or Linux.
Please note: Daren creates an SD card image that is loaded when CSpect is started. For many projects this is not necessary as you can transfer .nex and .sna files directly from DeZog to CSpect.
Cesar Wagener Moriana
Date: Dec-2019, DeZog 0.9 (Z80 Debug), ZEsarUX
Here is an older (but still great) tutorial from Cesar Wagener Moriana. He documented how he put all things together. It describes how to setup an integrated development environment for ZEsarUX with DeZog. It deals with setting up
and is available in English, Spain and German here.
Please note: The tutorial is a bit outdated, it uses 'z80-debug'. This was the former name of the project. It has been renamed to 'dezog'. This means especially that in the launch.json files you need to change 'z80-debug' to 'dezog'.
Nevertheless Cesar (W. M.) also shows how to setup the system under Windows and explains a few features of z80-debug/DeZog so that it is a great advice to get you started.