Raspberry Pi Floppy emulator

A good friend passed on this link.  And what an amazing thing!

Floppy interface board

So basically a Raspberry Pi (which can be had for sub $50 USD), running a bare metal program can emulate the control signals of an Amiga floppy drive.  It reads disk files from a flash card, and serves them to the Amiga.  It can even kickstart an Amiga 1000.

I know that floppy emulators have been an on/off hot topic, but this is pretty interesting!

And of course it has a DIY angle to it as well.

Here is a video of it in action:

 

EEVblog Vintage Teardown Tuesday, the Commodore Amiga 500!

I’m still a bit amazed the disks still work!  A nice, if not long teardown video, showing some of the mechanical problems with old Commodore kit, where connectors aren’t well connected to the PCB all too well.  I’ve only seen this pop up on G+, but I thought I’d pass it along.

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Can any Chrome users test this link?

http://vpsland.superglobalmegacorp.com/janus3/#dungeon

You can now easily download the scriptable Amiga emulator, and even better inject your own ADF’s and whatnot. Naturally you’ll want the AROS ROM’s one & two. You can even download my ADF.

It may take a minute to boot, but you should get something like this:

Dungeon for Amiga

Dungeon for Amiga

This is a bootable diskette with the version of Dungeon I built using DICE.

NetBSD 1.0 on the Amiga

NetBSD's old logo

NetBSD’s old logo

So while I was on the path of running some ancient Linux on the UAE Amiga 3000 emulator but without any real luck.  So for the heck of it I figured I’d give NetBSD a whirl.  Much like Linux, the first platform other than the i386 to get some mainstream love.

While 4.4 BSD had been adding support for the m68k via the HP 9000-300 series based workstations, the Amiga was something that was sold retail, and could be put in the hands of hackers, rather than lab rats..

So yeah, NetBSD started to integrate Amiga patches as of NetBSD 0.9 as it says from the install notes:

This version is strictly for the kernel hackers among you, there’s no sense in `normal’ users trying to install it, possibly killing their other partitions, facing kernel panics and not knowing what to do. Please keep that in mind, if you feel like going on…

So maybe I’ll try to bring it back to life some time now that I can at least run NetBSD 1.0 .. Or maybe I’m getting ahead of myself.

Installing NetBSD 1.0 on the Amiga is somewhat straight forward, providing you are doing this from a new Amiga.. First just create a small-ish (15MB? lol) partition for AmigaDOS, and make sure it is bootable.  The work partition should be big enough to hold the compressed packages of NetBSD, I went with 60MB, while NetBSD 1.0 is a mere 15MB, well compressed of course.  After that you’ll want to create a ‘root’ partition of say 65MB, a 32MB swap partition and a giant /usr partition.  I created a 384MB virtual hard disk, so my remainder is 209MB which is more than enough.  From there you have to make sure that they are not set to auto mount, and edit the filesystem type to be the following:

root partition  : 0x4e425207
swap partition  : 0x4e425301
other partitions: 0x4e425507

Where the ‘other’ is of course the /usr partition.  Then with that in hand it is a simple matter of loading the boot loader from within AmigaDOS.  The one weird thing I found is that while this part goes all fine,  later on under NetBSD you can only mount AmigaDOS partitions read only, so how do you get a new kernel back onto the Amiga side?  I suppose a working network, and a 2nd machine.. Which would make sure, and of course NetBSD was built with the idea that everyone was collaborating over the internet so people would have net access.

So basically from within AmigaDOS you kick off the bootloader, kernel, and shove in a ‘root filesystem‘ diskette.  Next thing you know we are going through the install where it’ll pick up the partition tags, format the disk, and go ahead  and install..  Again another ‘trick’ is the partitioning scheme where NetBSD maps in the AmigaDOS partitions into NetBSD space.  My install looks like this form the NetBSD side:

NetBSD slices

NetBSD slices

It may not seem too obvious but back here the ‘a’ partition is the root, ‘d’ is the AmigaDOS operating system partition while ‘e’ is the work partition where our install was saved. From there it really is NetBSD and it just acts like any other NetBSD.  So of course I could prattle endlessly about this, how historic it is that NetBSD on the Amiga shows that the older hp300 port could not only be adapted to new platforms, but even eventually extended to support the 68040 processor which had a different and incompatible MMU.

For those of you are are impatient, you too can run NetBSD 1.0!  You can find a pre-installed image here. And just use the prior exe & config from the WinUAE beta that included MMU support.  Just alter the config so that it picks up the NetBSD disk.

NetBSD 1.0

NetBSD 1.0

The only catch I’ve seen so far is that trying to bring up the ethernet adapter hangs the system.  Sadly I don’t have any fix for this as of yet…. (edit: yes beta 4 and beyond work fine!)

le Retour des AMIX de l’impact Amiga..

Screen Shot 2013-01-21 at 5.31.43 PM

I thought it was cool, but a French Amiga fan site, linked me and sent a bunch of traffic, amigaimpact.org.  Now I know what you are saying, I can’t read French! .. Well it is 2013, and google translate doesn’t do such a bad job of mangling les Francais..

Something like this.  I know, despite all the French I took in school, I’m lucky enough if I can get directions, or order food…

AMIX

AMIX Ad

AMIX Ad

Back in 1990 Commodore took the Amiga in a new direction with it’s new Amiga 3000, by commissioning a port of A&T SYSV Unix to the Amiga. Taking advantage of the 3000’s 68030 CPU and 68881 Math coprocessor, along with its integrated SCSI controller. It certainly was the hallmark of typical UNIX machines of the time.

When originally announced there was some big interest in the platform by SUN, as their original SUN-1, SUN-2 & SUN-3 lines of workstations were all 68000 based machines, and being able to rebrand a mass produced Commodore model would have been a good thing, however the deal ultimately fell through.  The machine would have been the Amiga 3500, which later became the Amiga 3000T.

Another thing to keep in mind is that SUN’s SYSV (Solaris) was targeted to the SPARC processor, and it is unlikely that they would benefit from selling a 68030 based machine in 1991.

Typical of the time, AMIX installs from a set of boot floppies, and then pulls the rest of the installation from a tape drive, such as the A3070.

AMIX was released at a time when the UNIX world was rapidly moving to RISC processors, SUN had their SPARC, SGI had their MIPS, IBM and their POWER, Motorola built UNIX machines around their 88000 RISC processor, NeXT was also going to move to the 88000 until they gave up making their own hardware and shifted to a software company.  So who would want a then dated 68030 based machine when the industry had made their first steps into the world of RISC computing.

So how does it measure up?  Well it is SYSV, and if you’ve seen one, well honestly you’ve seen them all.  What is kind of neat is that AMIX includes OpenLook and a C compiler, which is kind of a rarity for the period.

Another flaw was that when the 68040 processor was released it’s MMU was incompatible with the 68030, and the VM subsystem for any UNIX would have to be rewritten.  While NetBSD can run on both the 68030 and 68040, AMIX never was updated, and so it can only run on 68030 based machines.

AMIX never did get any critical traction, and slipped into oblivion with the death of Commodore.

Up until recently it was impossible to run AMIX in any emulator, but there has been a lot of work on the ARANYM and Pervious emulators which included doing 68030 MMU support for the possibility of running early versions of NeXTSTEP. Toni Wilen was able to adapt their work onto WinUAE and it is not possible to run AMIX.!

Reading through this thread,  I was able to put together the needed bits, and get it running under CrossOver, by using the pre-configured settings for WinUAE, and replacing the exe with the new beta exe, the supplied hard disk image from amigaunix.com and I was up and running in no time!  The only real change from the config was to change the SCSI ID of the hard disk from 0 to 6.

Screen Shot 2013-01-13 at 8.48.54 PM

AMIX starting up on WinUAE

The default password is wasp.  I thought it was kind of interesting that AMIX includes ‘dungeon’.  really cool!

Open Look on AMIX

Open Look on AMIX

I am unsure of how to enable the high resolution graphics, but sadly the Amiga known for its multimedia capabilities, AMIX with stock graphics runs in monochrome.  Such a major underwhelming thing.

Oh well, for anyone inclined you can now run AMIX, and enjoy another dead SYSV.

Floppy emulation on the Commodore Amiga

Well for some unknown reason the floppy drive in my Amiga just stopped working.  I managed to find a drive out of an Amiga 500, but it too didn’t work.. I really don’t know if it is the controller or if it is the drives.  And I’m hesitant to sink £100 into a machine that for all I know could have a dead controller.

So this means while I do have the Compact Flash working as a hard disk, I am unable to load an old favorite Captain Blood.  Maybe I am more of a sucker for the Jean-Michael Jarre resampled sound track ethnicolor. Or maybe there is just something redeeming about blowing up random planets.

Then while digging around DICE, I looked at its examples, and one of them was the exec_dev one, FMS a floppy emulator!  I built the example installed the driver, and using it resulted in a nice crash in both AmigaDOS 2.04 and 2.1 .. I had to wonder if this was more so geared to AmigaDOS 1.3 ..?  A bit of googling around and I found an updated version, fms_20.lha.  Installation is a little cumbersome as you have to manually copy in the device driver, and then setup a mountlist describing the devices in question, which really reminded me the “fun” of 4.3 BSD’s disktab.

Another weird thing is that AmigaDOS 2.1 has the FastFileSystem driver built in, so I had to remove those lines…

Using an ADF I found (since there is no way I can read the physical disk now..) I was able to use DMS to make an image on an emulator, copy it onto the flash, then re-DMS it out on the emulated floppy diskette.  Thankfully this game doesn’t use any weird custom filesystem so it was easy enough to mount the disk, and run the game from the emulated floppy.. Or at least launch it.  Trying to use it however resulted in the game just crashing.

Some more digging with a hex editor showed that the string “DF0:” was strewn all through the executable, so a few minutes, and I changed them all to “FF7” and now the game plays properly.

Captain Blood on my Amiga 600

Captain Blood on my Amiga 600

I wonder if it is possible to load the bootblock from one of these custom filesystems then use a virtual void pointer in DICE C, and execute the bootblock directly?  I’ll have to experiment.