FUZIX (Unix-like OS) ported to the ESP8266

Well here’s some really interesting news. I have a job set-up to update “interesting” GitHub projects to local disk on a daily basis, so I can just do a quick listing every morning to see what, if anything, has changed. This morning the FUZIX project flagged changes (FUZIX is a minimal, unix-like OS for very small, resource-limited micros, which started off being targeted at the Z80 series). When I checked the repository to see what the updates actually were, I found:-

drwxrwxr-x 10 gaijin gaijin 20 Feb 18 05:38 ..
-rw-rw-r-- 1 gaijin gaijin 11536 Feb 18 05:38 Makefile
-rw-rw-r-- 1 gaijin gaijin 273 Feb 18 05:38 .gitignore
-rw-rw-r-- 1 gaijin gaijin 35670 Feb 18 05:38 filesys.c
-rw-rw-r-- 1 gaijin gaijin 252 Feb 18 05:38 dep.mk
drwxrwxr-x 2 gaijin gaijin 6 Feb 18 05:38 cpu-armm0
drwxrwxr-x 2 gaijin gaijin 24 Feb 18 05:38 platform-esp8266

Which led, in turn, to David Given’s marathon videos (there are roughly 30-hours of keyboard-bashing and puzzling-out-loud available right now, with another five videos still to be released on a daily basis) detailing his work to port FUZIX to the ESP8266. David’s web site has some further explanation of how far along the port currently is, along with some pre-compiled, loadable binaries for the ESP8266 (I haven’t had time to try them yet). All of David’s work is available from his GitHub repository.

You will need to attach an SD card to get the full FUZIX experience, but David says it is reasonably speedy on the ESP8266, with a boot time of just 4 seconds.

|�l�c|����{���B�p�n�dNn���cp��cl r$p�N�s����cN�|����B�|�N�l��l�Nl�d Nr���N��{$�o�nod���no��rdp�n���l"o�|����p��no�$�$�no$�{$or���o� �n�2NNl��|�N��lp�N��d�#n�|���b��Nn�d�l �oo$�{lor���N$�$sےNl��FUZIX version 0.4pre1
 Copyright (c) 1988-2002 by H.F.Bower, D.Braun, S.Nitschke, H.Peraza
 Copyright (c) 1997-2001 by Arcady Schekochikhin, Adriano C. R. da Cunha
 Copyright (c) 2013-2015 Will Sowerbutts will@sowerbutts.com
 Copyright (c) 2014-2020 Alan Cox alan@etchedpixels.co.uk
 Devboot
 80kB total RAM, 64kB available to processes (15 processes max)
 Enabling interrupts … ok.
 Scanning flash: 2591kB: hda: 
 SD drive 0: hdb: hdb1 hdb2 
 Mounting root fs (root_dev=18, ro): warning: mounting dirty file system, forcing r/o.
 OK
 Starting /init
 init version 0.9.0ac#1
 fsck-fuzix: 
 
 login: root
 Welcome to FUZIX.

David notes in the README (contained in the binary tar-file) that the system does have some limitations; first and foremost is that it is almost unusable running from flash, so you really do need to wire up an SD card (pinouts for this are included in the same README). Here is his ToDo list:-

  • userland binaries can’t find their error messages.
  • CPU exceptions should be mapped to signals.
  • single-tasking mode should be switched off (which would allow pipes to work).
  • someone needs to overhaul the SD SPI code who understands it.
  • not all the ROM routines are hooked up to userland binaries.

Right, I’m off to look for an SD card and a spare ESP. See you later!