FujiNet and Atari800 Emulation

Running a virtualized Atari emulation on modern hardware with FujiNet used to require running the amazing Altirra Atari emulator. One issue however- Altirra is only released as a Windows app. Wine has worked for Linux and Mac users to run applications like Altirra on the best platforms but it’s still a bunch of hoops to leap thru and it takes a bit of cycles to run all those layers just to run a 64k 6502 based system.

But we have choices. The other Atari 800 emulator is called atari800 (a800). It was written in 1995 by David Firth and currently maintained by Petr Stehlik. Atari800 was one of the first, if not the first, portable (written in C) emulator for the Atari 800 personal computer.

Recently the FujiNet Core team contributor Mozzwald grabbed the a800 source and wrangled it till all the SIO commands could be redirected to UDP on the local system to a waiting FujiNet POSIX service (called FujiNet-PC). Together this allows the a800 emulation to run natively on your Macintosh and access a Fujinet just like a real physical Atari and FujiNet.

I then took the small step of just building a800 with SIO support for you and providing a zip file (below) that has the binary as well as the binary build for FujiNet-PC. Download, unzip, run them both and enjoy the FujiNet experience on your Mac today.

Download my build:

Download from my Dropbox

Install SDL 1.2

Note:

• You must install SDL1.2 if you don’t already have it installed on the Mac
• Always start the FujiNet PC – it will wait for the atari800 to start

$ brew install sdl12-compat

Note: if you need brew check out the directions: Brew

Run the FujiNet

See below if OSX harasses you about running it…

$ cd atari800-fujinet-5.2.0-fn1

$ ./run-fujinet 
Starting FujiNet
16:05:11.386078 > 
16:05:11.386834 > 
16:05:11.386837 > --~--~--~--
16:05:11.386839 > FujiNet v1.5.0+git-6e4bc637 2025-04-07 21:46:30 (ATARI) Started @ 1
16:05:11.386970 > Detected Hardware Version: fujinet-pc
16:05:11.386974 > SPIFFS mounted.
16:05:11.387020 > SD mounted (directory "SD").
16:05:11.387043 > fnConfig::load "fnconfig.ini"
16:05:11.387114 > fnConfig::load read 1242 bytes from config file
16:05:11.387182 > Reading wifi section
16:05:11.387248 > disk UNMOUNT
16:05:11.387267 > FileSystemSPIFFS::filehandler_open /autorun.atr rb
16:05:11.387324 > disk MOUNT
16:05:11.387344 > ATR MOUNT
16:05:11.387587 > mounted ATR: paragraphs=5760, sect_size=128, sect_count=720, disk_size=0
16:05:11.387635 > PCLINK[1] MOUNT "SD"
16:05:11.387652 > Creating a default printer using FS_SDFAT storage and type 1
16:05:11.387690 > SIO SETUP
16:05:11.387692 > SioCom::set_serial_port ,1,1
...
16:05:11.387708 > Starting web server http://0.0.0.0:8000
16:05:11.388728 > Error starting web server!
16:05:11.388731 > DummyWiFi connect to SSID "Dummy Cafe"
16:05:11.787536 > Setting up NetSIO (localhost:9997)
16:05:11.787685 > Resolving hostname "localhost"
16:05:11.790162 > Resolved to address 127.0.0.1

[a bunch more output follows, you can ignore it]

---

Run the Atari800

Open a new terminal window and run the Atari emulator

$ ./atari800 -xl -netsio -win-width 1024 -win-height 768
Using Atari800 config file: /Users/dillera/.atari800.cfg
Created by Atari 800 Emulator, Version 5.2.0

Keyboard mapped to emulated joystick 0
Requested resolution 336x240 is not available, using 640x480 instead.
Video Mode: 1008x720x32 windowed without vsync

[a bunch more output, you can ignore it]

Important Keys:

F1: Show A800 Config
F2: OPTION (boot from CONFIG)
SHIFT-F5 – Cold Boot (go back to CONFIG)

Troubleshooting

I have not signed this code, apple will do its thing and not allow it to run the first time….

Go into System Prefs | Security and tell OSX to do it. You only have to do this once.