BeBox

BeBox is a Haiku application that emulates Be Inc.'s BeBox, the dual-processor computer that BeOS was born on. It runs both PowerPC models from their original boot ROMs, with BeOS for PowerPC from Developer Release 6 through R5.0.3. It also runs the Hobbit prototypes that came before them, built around two AT&T Hobbit processors, with Be's 1993-94 system from their surviving disks.

Model	Processors	Bus
BeBox Dual603-66	two PowerPC 603 at 66 MHz	33 MHz
BeBox Dual603e-133	two PowerPC 603e at 133 MHz	33 MHz
Hobbit prototype (1993-94)	two AT&T 92010 (Hobbit) at 25 MHz	BeBus, 25 MHz

The window shows the emulated screen between the two front panel LED columns (the "blinkenlights"), sixteen light pipe segments each: a CPU load bar of fifteen LEDs over the power LED (left) or the disk LED (right), lime and amber like the real ones (or red and green, if you prefer).

What is emulated

• Both processors (a PowerPC 603/603e interpreter with the 603's software TLB), the MPC105 bridge, the BeBox interrupt and CPU control registers.
• Boot ROM: the nub and main ROM in a writable flash (BeOS's ROM updater works), NVRAM and real time clock.
• Video: Number Nine #9 GXE64 (S3 Vision864, AT&T 21C498 RAMDAC) with its graphics engine, the default; or Cirrus Logic CL-GD5434. 640x480 to 1280x1024, 8 and 32 bits per pixel (what the BeOS drivers offer).
• Sound: Crystal CS4231A codec, played through the Haiku media kit.
• AT keyboard and PS/2 mouse; four game ports (axes and buttons).
• Storage: NCR 53C810 SCSI (disks and CD-ROMs on IDs 0-6), IDE, floppy.
• Four serial ports: to a console window, a TCP server or client, a host serial port or a log file.
• Ethernet: an NE2000 compatible ISA card on a private network behind the host (NAT, through libslirp): the BeBox reaches the host and the Internet, and host ports can be forwarded to it.
• Shared folders: a Haiku folder appears to BeOS as a SCSI disk it can read and write; the changes come back to the folder when BeOS shuts down.

Not emulated yet: the parallel port, GeekPort, MIDI and infrared ports.

What you need

• The BeBox boot ROMs, which are not included: bootnub.rom (16 KB) and bootmain.rom (Be Boot ROM 1.1d7) from a BeBox, in a folder of your choice.
• BeOS for PowerPC: CD images (ISO, BIN/CUE or Toast).
• For the releases with the Be File System (Advanced Access to R5): a newer boot ROM, which the Preview Release 2, R3 and R4.5 CDs carry as /beos/etc/bebox_bootmain.image (Advanced Access, Preview Release 1 and R5 use one of those). BeBox extracts it for you (see below).

Getting started

1. Open Machine > Preferences > ROM & NVRAM and choose the folder with the ROMs. For a BFS release, choose its CD image as Boot ROM image: BeBox copies the boot ROM from the CD (PR2's also boots Advanced Access and PR1).
2. In Storage, put the CD image on a SCSI ID as CD-ROM (ID 3 is the classic choice), and give another ID a disk for installing: Choose... opens a file panel whose New disk image... button makes one right there (in the folder the panel shows) and puts it on that ID.
3. Machine > Power on. The newer boot ROMs stop at their boot menu when no boot volume is set yet: press Return.

Changes to the hardware restart the machine; a new floppy or CD goes into the running one. A disk set without a file is turned back into "None" when the preferences are saved (a CD-ROM drive stays, empty).

The Hobbit prototype

Before the PowerPC BeBox, Be built its machine around two AT&T 92010 "Hobbit" processors, three AT&T DSP3210 signal processors and the BeBus. A few prototypes survive with their disks, running Be's 1993-94 system: a window server, a console, the Browser and its dock.

What is emulated:

• Both Hobbit processors (an interpreter written from AT&T's programmer's reference: the stack cache, the MMU, the timers, the event sequences).
• The board: its I/O and interrupt registers, the processor resets, the floppy DMA; the PC compatible I/O chips (keyboard and PS/2 mouse, real time clock, two serial ports, floppy) and the NCR 53C94 SCSI controller.
• The video card: a Trident VGA with an XGA style graphics engine on the BeBus (640x480 or 800x600, 256 colors, as the window servers set it).

Not emulated: the three DSPs and what hangs off them (sound, the telephone and modem), the Ethernet card, the joystick controller and the parallel port. The system starts without them (its sound server reports an error).

No boot ROM of these machines survives, so BeBox does the boot ROM's job: it loads /system/kernel from the boot volume (the floppy if one is inserted, else the SCSI disk with the lowest ID) and starts it. To run one:

1. In Preferences > Machine, choose Hobbit prototype and 4, 8, 16, 20 or 32 MB of memory (the sizes its kernel knows).
2. In Storage, put a Hobbit disk image on a SCSI ID as a disk. To run a kernel of your own instead of the disk's, choose it in ROM & NVRAM > Hobbit kernel.
3. Machine > Power on. The kernel reports its progress on serial port 1 (give it a console window in Serial to watch).

Notes:

• The November 1994 disks start /system/Browser, which they have as /system/browser: the console comes up instead (the real machines did the same). Type /system/browser & in it to start the Browser.
• The floppy drive is the kernel's drive 1.
• The system writes to its disk (swap files and more): keep a copy of your images, or use them through QCOW2 overlays (bebox-img create -b IMAGE OVERLAY.qcow2).
• The front panel lights are hidden: the Hobbit's kernel drives none.

Installing from the floppies

The installer floppy and disks 1of7 to 7of7 install the November 1994 system (the one on the "pixels" disk) on a new disk. The installer floppy has no window of its own: its /system/Browser copies a minimal system (kernel, servers, shell, /Installer) from the floppy to the first hard disk, without asking and without showing anything but the pointer. Boot it only with the disk to install on: it replaces the system files of any other Hobbit disk it finds.

1. Put a copy of a Hobbit disk (or an overlay of one) on SCSI ID 0, and a new disk image on ID 1 (in Storage, the ID's file panel has New disk image...; 120 MB works, the original disks have 120 to 170 MB). Power on, type /bin/format in the console, choose the SCSI disk with ID 1, give the volume a name, then 0 to leave. Power off.
2. Take the Hobbit disk off ID 0 and put the new disk there instead. Insert the installer floppy and power on. After about a minute (the pointer is all you see), power off and eject the floppy.
3. Power on: the console comes up from the new disk. Type /Installer, click Begin, then insert 1of7 (Media > Insert floppy...) and click Continue, and so on up to 7of7. The Installer then uncompresses, verifies and extracts the archive (a few minutes), and Install finishes: "Installation complete". When it starts uncompressing, the console shows VOLUME:/_install_/archive.Z: System Error 0: harmless, and a real Hobbit did the same (compress deletes the archive while it still has it open, which this file system refuses; the Installer removes it at the end).
4. Restart, and type /system/browser & to start the Browser.
5. Optionally, run /Installer again with update.img as disk #1: Be's update of 28 November 1994 (a fixed storage_server and the Phone answering machine's spoken prompts in /system/phone, as on the "be" disk).

Profiles

Each release likes a machine of its own (its boot ROM, its disks, maybe the 133 MHz model), so the machine is kept in a profile: everything in the preferences except Keyboard & mouse and the LED look, plus the boot ROM flash (with the boot ROM updates BeOS installs) and the NVRAM (with the boot volume). Machine > Profile lists the profiles to switch between (a running BeBox restarts with the other one), and has New profile... (a copy of the current profile, under a name like "BeOS5 133 MHz" or "DR8 66 32 MB"), Rename and Delete. The status line shows the current profile. Profiles are folders in ~/config/settings/BeBox/Profiles/; the settings from before profiles became the profile "Default".

Release	Boot ROM	Boots from CD	Installs to disk
DR6 (BeOS 1.1d6)	original 1.1d7	yes	yes
DR7 (BeOS 1.1d7)	original 1.1d7	yes	yes
DR8	original 1.1d7	yes	yes
Advanced Access	PR2's	yes	yes
Preview Release 1	PR2's	yes	-
Preview Release 2	from its CD	yes	yes
R3	from its CD	yes	yes
R4	from its CD	yes	yes
R4.5	from its CD	yes	yes
R5.0.3	R3's	yes	yes

"-" means not tried yet. The DR8.2 image is a Mac updater. The boot ROM from the R3 CD works with every release tested here, so one profile with it can run them all.

DR6 predates the 1.1d7 boot ROM: BeBox hands its kernel the PCI device table in the older format it expects. Install it as the CD says: boot the CD, run the Installer from the dock, format the SCSI disk ("Format:" in the left pop-up menu), then install onto it and make it the startup disk. DR6's mouse driver moves the pointer twice as far left and down as right and up (that is DR6, not the emulation). The Developer Releases' date prints the year as years since 1900 (126 for 2026).

The BeBox takes 8 to 512 MB of memory (Preferences > Machine). Be's FAQ promised up to 1 GB with 64 and 128 MB SIMMs, though Be only tested 32 MB SIMMs; the boot ROM's memory test accepts 512 MB at most (it turns off every 128 MB bank but the first, so 1 GB would show up as 128 MB). R3 and R4.5 see and use all 512 MB. DR8 boots with up to 96 MB: from 128 MB on its kernel stops at "swap_file_offset: should never happen". At the other end, DR8, R3 and R4.5 all run in 8 MB (a pair of 4 MB SIMMs), but the R4.5 boot ROM does not: it puts its heap at half the memory, which with 8 MB is right on top of its own code, so it crashes before loading anything. Boot R4.5 in 8 MB with the R3 boot ROM. The memory test at power on takes 2 s per 32 MB on the 66 MHz model (32 s with 512 MB) and half as long on the 133 MHz one.

Using it

• While the window is active, the keyboard belongs to the BeBox. Click the screen to capture the mouse; the host key, right Control, releases it. Keyboard & mouse in the preferences picks another host key and sets the mouse speed.
• Game ports in the preferences connects host joysticks to the four sticks (two per game port, as with Y cables).
• The status line shows the floppy, CD and hard disk (with the disk activity); click the floppy or the CD to insert one.
• When a disk image cannot be written (a full disk, say; BeOS then gets a write error) or the profile's flash and NVRAM cannot be saved, BeBox says so in an alert and for a while in the status line.
• Media inserts and ejects floppies and CDs while the machine runs (for a CD, give a SCSI ID a CD-ROM drive in Preferences > Storage; it may be left empty). BeOS mounts a CD by itself a few seconds after it goes in. A CD that replaces another one stays out for six seconds first: BeOS checks the drive every five seconds and only notices the new disc after it has seen the drive empty. A CD that BeOS ejects (CDPlayer's Eject button, eject) leaves the drive empty.
• Machine has the power, reset and interrupt switches, and restarts with the boot menu or with kernel debug output on serial port 4 (that holds F1 at power on, as on a real BeBox, until the boot ROM starts writing to serial port 4). Send Ctrl+Alt+Delete gives BeOS the keys Haiku keeps for itself: BeOS R3 and later show their Team Monitor, and restart when it is sent again.
• The two processors run on two host cores when both are busy (Preferences > Advanced, on by default): up to nearly twice as fast, which the 133 MHz model needs on slower computers. While other programs keep the computer's cores busy, two cores are slower than one (each processor keeps waiting for the other), so BeBox then runs both on one core and tries two again every few seconds. The status line shows the speed in percent of a real BeBox.
• Speed (Preferences > Machine) is the processors' speed: 50%, 100% (a real BeBox), 200% or as fast as the computer allows. BeOS's clock, the cursor's blinking and the keyboard's repeat keep real time also with faster processors. When the computer cannot keep up, faster processors give back their extra speed first; at a real BeBox's speed the whole machine runs slower for a moment and catches up (the sound output then keeps more in reserve).
• Tools > Serial console shows a serial port connected to a console.
• View shows the screen at actual or double size or fitted to the window, and shows or hides the LEDs. Full screen (or the host key with F, also while the BeBox runs) leaves only the screen, and the LEDs at the sides if they are shown; the host key with F again brings the window back. Full screen scaling makes the screen fill the display in its proportions (smoothly scaled), or keeps its pixels sharp: the largest whole multiple that fits, or actual size (1:1), with black around it.

Network

User mode networking is built in and on by default when BeBox is built with libslirp; start with --no-net to omit the Ethernet card. Nothing else runs on the host. In Preferences > Network, turn on the Ethernet card (port 300h, IRQ 5 by default, as Be's software expects). In BeOS's Network preferences, add a "Novell NE2000 compatible adapter (ISA)" with the same port and IRQ, and choose DHCP (R4.5) or set IP 10.0.2.15, mask 255.255.255.0, gateway 10.0.2.2 and DNS 10.0.2.3 by hand. The host is 10.0.2.2 from the BeBox.

Forwarded host ports (tcp:2121:21, tcp:2323:23) make services running in BeOS reachable from the host. The SDL frontend binds these listeners to 127.0.0.1, so only the host can reach them. For example, with BeOS's FTP server enabled (FTP_ENABLED = 1 in config/settings/network):

curl -u USER: -T file.txt ftp://127.0.0.1:2121/
curl -u USER: ftp://127.0.0.1:2121/

The user is the BeOS account (anonymous is rejected); a blank password is written as USER:. Passive mode works because the emulator forwards the data port from the guest's 227 reply on the fly (libslirp's own FTP emulation is bypassed, as it is broken for host-forwarded connections in libslirp 4.9). Active mode is not supported.

Processor speed

The SDL frontend takes --cpu-speed X (through 4 on the 66 MHz model and 2 on the 133 MHz model). It is a shortcut for the speed limit: X = 2 means 200% of a real BeBox's processors. Emulated time follows real time, so BeOS's clock, timers and keyboard repeat are unaffected; the processors simply get more instructions per emulated second. How much more is limited by the host: when it cannot sustain the requested speed, the processors give back the extra speed (as the Haiku frontend does) instead of letting the guest clock drift, so a request above what the computer can run settles at what it can.

--cpu-speed-forced X is the same, but the processors stay at X times a real BeBox even when the computer cannot keep up. Emulated time then runs slower than real time (BeOS's clock falls behind), which is what "overclocking" a real BeBox would not do, so it is off by default. The instruction rate is still limited by the computer, but the guest sees processors that are X times as fast, which suits benchmarks and software that checks the clock.

--stats (or F9 while running) shows the processors' speed and instructions per second in the top-left corner: CPU <MHz> is the speed in effect (the set speed with --cpu-speed-forced, the achieved speed otherwise), and <MIPS> is the measured instruction rate. When a program keeps the processors busy, MIPS is the honest figure for how much work gets done per real second.

Shared folders

In Preferences > Storage, make a SCSI ID a Shared folder and choose a Haiku folder. At power on BeBox copies the folder, with its attributes (file types, icons), to a fresh BFS volume that BeOS mounts like any disk; the releases with BFS (Advanced Access and later) can use it. When BeOS has shut down (Be menu > Shut Down) and the BeBox is powered off, BeOS's changes go back to the folder: new and changed files, attributes, deletions. A file changed on both sides meanwhile keeps the Haiku version, and BeOS's is saved next to it as "NAME (BeBox)". If BeOS did not shut down cleanly, the volume is kept and given back to BeOS at the next power on, so that it can repair it first. The same happens when a change cannot be made (a file the folder refuses, a damaged volume): BeBox says so, deletes nothing in the folder and tries again at the next power on. As the whole folder is copied at every power on, keep it small: the BeBox starts once the copy is done (the status line says so meanwhile, and the window stays usable), and quitting waits for BeOS's changes to be back in the folder.

Disk images

Hard disks are raw images or QCOW2 images, which only take the space that is written (thin provisioning) and can be overlays of a backing image. bebox-img manages them, and reads files from BeOS volumes (BFS) and from the Hobbit prototypes' disks:

bebox-img create [-f raw|qcow2] [-b BACKING] FILE SIZE
bebox-img info FILE
bebox-img check FILE
bebox-img convert [-O raw|qcow2] SOURCE DESTINATION
bebox-img ls IMAGE [PATH]
bebox-img attr IMAGE PATH
bebox-img extract IMAGE PATH OUTPUT

For example bebox-img extract "BeOS Release 3 PowerPC.iso" /beos/etc/bebox_bootmain.image r3.rom.

bfsexplorer IMAGE browses the first BFS volume in an image and copies files between it and the host, with an ls-style listing:

make -C tests/linux FAST=1 out/fast/bfsexplorer
tests/linux/out/fast/bfsexplorer disks/R5.qcow2

The first push creates IMAGE.bfs-overlay.qcow2, backed by IMAGE, and writes there; the original image is not changed. Boot the overlay as a disk (--scsi1-disk disks/R5.qcow2.bfs-overlay.qcow2) to use the changes. --no-overlay writes IMAGE directly; --overlay FILE chooses another overlay path.

--commit-on-exit merges the overlay into IMAGE when the REPL exits, then removes the overlay. Only clusters allocated in the overlay are copied back, so this does not rewrite the whole disk; the overlay remains if the merge fails. A failed push is not committed. This changes IMAGE, unlike a normal session.

dir [PATH]        list a BFS directory (default: BFS cwd)
cd PATH           change the BFS directory (~ is /home; /boot is /)
pull SRC [DEST]   copy a BFS file or symlink to the host
push SRC [NAME]   copy a host file to the BFS directory
ldir [PATH]       list a host directory
lcd PATH          change the host directory
pwd, lpwd         print the BFS / host directory
help, exit        show help / leave

push still rewrites the whole BFS volume, including attributes and symlinks, but does so in the overlay, so IMAGE remains unchanged. The overlay grows with the rewritten data. Stop BeOS before pushing. The rewritten volume has no index directory, so attribute queries are lost; hard links are not preserved.

On a Hobbit disk, extract also copies whole directories (/ for the whole disk) into a new folder, keeping the files' dates, and ls shows the files' types and creators: bebox-img extract hobbit-930800009.img / pixels. No BeOS release reads the Hobbit's file system (DR6 to DR8 have a later, incompatible version of it, the others BFS), so this is the way to its files: extract them, then give the folder to a BFS release as a shared folder. The Hobbit's programs do not run on the PowerPC; its sources, headers, text and pictures are what is useful.

Scripting

The machine window answers hey:

hey BeBox get Running of Window BeBox          # also set ... to true/false
hey BeBox get Speed of Window BeBox            # percent of a real BeBox
hey BeBox get LedLevels of Window BeBox        # left, right (0-15)
hey BeBox get SerialLog 4 of Window BeBox      # a console port's output
hey BeBox set Floppy of Window BeBox to /path/disk.img
hey BeBox set CdRom of Window BeBox to /path/disc.iso   # "" ejects
hey BeBox set FullScreen of Window BeBox to true
hey BeBox type of Window BeBox with text=ls    # types on the keyboard
hey BeBox shot of Window BeBox with path=/tmp/screen.png

CdRom is the first CD-ROM drive, CdRom 3 the one on SCSI ID 3. Also get Mips, get EmulatedTime, get DiskLed, get AudioStats (the sound output's counters: underruns are gaps), get Problem (the latest storage problem, empty if none), get Profiles, get Profile and set Profile (switches, restarting a running machine), and the commands pwon, pwof, rset and cadl (Ctrl+Alt+Delete). Replies come after the action.

Command line

BeBox [--profile NAME] [--rom-dir DIR] [--boot-rom IMAGE] [--model 66|133|hobbit] [--kernel FILE] [--ram MB] [--video s3|cirrus] [--scsiN-disk FILE] [--scsiN-cd FILE] [--scsiN-share FOLDER] [--ide0 FILE] [--floppy FILE] [--net] [--net-forward SPEC] [--power-on] [--log CATEGORY=LEVEL] sets up the machine (the settings are kept; an empty FILE removes the device, or leaves the CD-ROM drive empty). --profile switches to a profile first, making it as a copy of the current one if there is none; the other options change that profile. --log writes the emulator's messages of a category (scsi, machine, ... or all) from that level on (error, warning, info, debug, trace) to the standard error, for a start from Terminal.

bebox-headless runs a machine without a window, for tests and debugging: serial ports to files or TCP, scripted keys and mouse clicks, screenshots, instruction traces, memory dumps and watches, and profiling (--stats: where the host's time goes and what the processors' slow paths did; --profile: the emulator's functions that take the time, on Linux). bebox-headless --help lists the options.

Building

macOS (CMake)

Requirements: CMake 4.4.2 or later, Xcode command line tools, and Homebrew packages sdl2, zlib (included with macOS) and libslirp (for user mode networking; optional).

brew install cmake sdl2 libslirp
cmake -S . -B build -DCMAKE_BUILD_TYPE=Release
cmake --build build
ctest --test-dir build --output-on-failure

The programs are written to build/:

• build/src/sdl/BeBox: the emulator window (BeBox --help lists the options).
• build/src/headless/bebox-headless: the machine without a window.
• build/tools/bebox-img and build/tools/bfsexplorer: disk image tools.

Options (-DNAME=VALUE on the cmake -S line):

Option	Default	Meaning
CMAKE_BUILD_TYPE	Release	Release or Debug
BEBOX_BUILD_SDL	ON	build the SDL2 emulator window
BEBOX_BUILD_HEADLESS	ON	build bebox-headless
BEBOX_BUILD_TOOLS	ON	build bebox-img and bfsexplorer
BEBOX_BUILD_TESTS	ON	build the test programs and register them with CTest
BEBOX_BUILD_BENCH	OFF	build cpu-bench (a benchmark, not a test)
BEBOX_WITH_SLIRP	ON	user mode networking through libslirp (off if not found)
BEBOX_SANITIZE	OFF	AddressSanitizer and UndefinedBehaviorSanitizer

Homebrew is found in /opt/homebrew. For another prefix, add it to the search path: cmake -S . -B build -DCMAKE_PREFIX_PATH=/path/to/prefix.

The test programs in build/tests/linux (qcow2-tests, bfs-tests, device-tests, hobbit-tests) run under ctest. cpu-unit-tests is built but not run by CTest: it needs PowerPC test images that are not in the repository.

Haiku

On Haiku (with haiku_devel, zlib_devel and libslirp_devel): make builds the app. Haiku is not part of the CMake build. package/build-package.sh builds the app and the tools and creates the package.

The emulator core is portable C++17 and is tested on Linux:

• make -C tests/linux check: processor tests (against qemu-ppc as an oracle), Hobbit processor tests, multiprocessor and device tests, QCOW2 tests (against qemu-img, also on a full disk), under AddressSanitizer and UndefinedBehaviorSanitizer.
• tests/tsan.sh: the threaded mode under ThreadSanitizer (the multiprocessor test and an R4.5 boot).
• tests/boot-regression.sh: boots each BeOS release headless (the media and installed disks go in work/) and the Hobbit disks (in Hobbit/), through throwaway overlays.
• tests/vm-test.sh user@haiku-host: builds the app on a Haiku machine and drives it with hey.

design/ describes the hardware and the emulator's design.

Authors

• Claude Opus 5.5
• John Rash

License

MIT, see LICENSE. The application icon (artwork/BeBox.hvif) is by zuMi, under the MIT License. The icons in artwork/icons come from Haiku's icon set (MIT, Haiku, Inc.). The BeBox ROMs and BeOS are not part of this project.