Requires a 64-bit Intel machine running OS X 10.9 (Mavericks) or later, or an Apple Silicon Mac.
Files for the latest release are here: https://github.com/tom-seddon/b2/releases/latest
If using macOS 13 (Ventura) or later on Apple Silicon, download the
b2-macos-13.0-applesilicon-XXX.dmg file.
If using macOS 12 (Monterey) or later, download the
b2-macos-12.0-intel-XXX.dmg file.
If using OS X 10.9 (Mavericks) or later, download the
b2-macos-10.9-intel-XXX.pmg file. The 10.9 version does not support
writing compressed videos, but is otherwise fully-featured.
You don't need to download any of the other files; the dmg contains everything required.
Open the dmg, drag b2 to your Applications folder, and run it from
there. (Running it from the dmg directly is unsupported, and it may
not work. I've had reports of odd behaviour when attempting it!)
On first run, you'll almost certainly get a warning about the developer being unidentified. To get around this, follow the instructions here: https://support.apple.com/en-gb/guide/mac-help/mh40616/mac
If you're a programmer, you might also want to try b2 Debug,
installed in the same way, an extended version with additional
debugging features for use when creating new
programs or investigating existing software.
The releases are created automatically, and it can sometimes take a day or two for the macOS version to appear.
If this happens, you can download an older version for now from the full list at https://github.com/tom-seddon/b2/releases. Please revisit after a day or two!
The first time you run b2 on newer macOS, you may get a warning about b2 wanting to receive keystrokes from any application. (This is due to b2's tracking of the Caps Lock key... it isn't trying to steal your data!)
Granting it access is optional, though necessary for the Caps Lock key to work in the emulator. Follow the prompts if you want to do this.
If you'd prefer to deny it access, the Mac's Caps Lock key will simply do nothing in b2. The default keyboard settings treat the Page Up key as Caps Lock, so you won't lose out in this case.
If you granted b2 keystroke access, this setting will get forgotten when upgrading to a newer version.
To fix this, go to System Preferences, Security and Privacy,
Privacy tab, Input Monitoring, and remove the entry for b2 by
clicking on its row and using the - button.
Run it again, and you should get the keystroke access warning.