Sunday, July 17, 2016

DF0 Selector on Amiga 500

Following on from my initial work on my newly received Amiga 500, I decided to install a DF0 selector, which enables me to select to boot DF0 from the internal floppy drive or boot DF0 from an external floppy drive, even under Kickstart 1.3!

The main benefit of doing this is so that you can boot a Gotek floppy drive emulator as DF0 without having to hack up the case to fit it internally!

So with this device installed you can boot demos and games ADF's from the Gotek connected to the external floppy drive port as if it was connected to the internal floppy cable. Very cool. Means it is easy to switch my Gotek to whatever Amiga requires it.

I picked up the DF0 Selector from a while ago, in preparation to doing this on the Amiga 1000, but since the Amiga 500 is here I thought I would set it up on that instead!

Here is the DF0 selector as delivered:

To do this installation, we need to remove the Even CIA chip from the Amiga 500 motherboard - here it is, shown just below the internal floppy drive cable connection:

Here is the chip safely removed:

Paying careful attention to the chip orientation, I place the even CIA chip on the DF0 selector socket connection as below:

I then install the DF0 selector back onto the Even CIA socket:

As a temporary measure I route the selector switch out through the left hand side expansion gap (same as I did for the Indivision ECS):

Close up view of the switch - flick the switch one way for DF0 to be the internal floppy drive, the other position for DF0 to be the external floppy drive (Gotek in my case).

Here is the Gotek - I also picked up a Gotek floppy drive connector (including power) from to neatly power the Gotek without the need of extra power supplies, etc. The power comes from the external floppy drive connector, as it used to do for the real external floppy drives back in the day!

Close ups of the new gotek floppy connector:

With the Gotek connected to the external floppy drive port and selected as DF0 using the DF0 selector I then fired up the Amiga 500.

I confirmed it booted the Gotek fine as DF0 straight into the selector.adf.

Now for the real test - some tracks demos which are hard coded to only accept DF0 - Scoopex's Mental Hangover demo is a nice choice that works with the 512k we have on this Amiga 500 - one of my favourite demo soundtracks too. It works!

I put the Amiga 500 case back on and pleased to say everything still works:

One thing that has been bugging me is the lack of memory - only having 512k memory limits what games and demos I can try out. But thanks to the ACA500 help is at hand!

When the ACA500 is connected, on booting the A500 the configuration menu appears to load the 3.1 or 1.3 configurations for cf card booting a hard disk. However, you can also choose to boot fast ram or chip ram enabled 1.3 configurations:

If I choose F4 to boot Fast RAM enabled 1.3 configuration, the system now have 2MB memory available! I booted up the Workbench 1.3 ADF from the Gotek to check this:


So now I can boot up 1MB plus demos on the A500 using the Gotek ADF's (or real floppies if I desire). This is Scoopex's Millennium demo from 2000 running from the Gotek via ADF as DF0 using the DF0 Selector:

I also tried out Ghostown and Whelpz's Sunglasses At Night, the final version demo from 2015 too - great stuff:

I am happy with this setup now on the Amiga 500!

Well, err, I might do some more with it - tempted to try the MAS MP3 Player hardware on it - Mp3's on an Amiga 500, hmmm, tempting to try it. If I can get a bit more memory and an A1200 accelerator to connect to the ACA500 I could try the Subway USB support too - ahh, so many things to muck around with on Amiga's in 2016!

Reached the end of the weekend and I now have a nicely running Amiga 500 I didn't expect to even have before it! Life is interesting for sure! :-)


  1. Great work Epsilon as always. It is a great pleasure seeing what you are able to do with this hardware...


  2. Awesome! This is exactly what I'm about to do as well. I might even get an external floppy drive and mount the Gotek in there.