Spectranet Emulation

Fredrick Meunier Sergio Baldoví

The Spectranet is an Ethernet network interface for the ZX Spectrum by Dylan Thomas. The interface can be activated via the Spectranet option on the Peripherals preferences dialog, and the state of its automatic page-in (disable) jumper controlled via the Spectranet disable option. If you’re going to be using the Spectranet, you’ll probably want one of the firmwares available from the Spectranet homepage (http://spectrum.alioth.net/doc/index.php) which is also where you can find more information on using the interface.

Installing the Spectranet firmware on Fuse is slightly more complicated than on a real machine, mostly because Fuse’s emulation doesn’t support DHCP. These instructions are correct as of 2012-01-26 — if you’re using a later firmware than this, things may have changed slightly.

The first thing you will need to do is to obtain a copy of the Spectranet installer as a .tap file (or similar). The installer is also available at the Spectranet site above.

Once you have a copy of the installer, start Fuse and tick the Spectranet option from the Options, Peripherals, General... dialog, and the state of its write protect jumper controlled via the Spectranet disable option. Once that’s done, open the installer file (use the Media, Tape, Open... command rather than File, Open... to prevent autoloading) and enter the following commands from BASIC:

CLEAR 26999

The screen should turn blue and you’ll see around 20 lines of message appearing as the firmware is installed, starting with “Erasing sector 0” and finishing with “Restoring page B”, and you’ll get the familiar 0 OK, 0: 1 at the bottom of the screen.

Now untick the Spectranet disable option from the Options, Peripherals, General... dialog and reset the Spectrum. You should see a very brief blue status screen, before the regular copyright screen appears with some Spectranet information at the top — there should be four status lines, starting with “Alioth Spectranet” and ending with the Spectranet’s IP address (which will be at this stage).

Now trigger an NMI (the Machine, NMI menu option) and you should get a white on blue Spectranet NMI menu with five options.

Select [A] Configure network settings — this should lead you to another menu, which will scroll of the top of the screen; don’t worry about this for now.

You’ll now need to set various options:

[A] Enable/disable DHCP — select N
[B] Change IP address — enter the IP address of the machine you are running Fuse on.
[C] Change netmask — enter the appropriate netmask for the IP address you selected above. If that doesn’t mean anything to you, try
[D] Change default gateway — enter the appropriate gateway address. If you don’t know any better, enter the IP address of your router.
[E] Change primary DNS — enter the address of your DNS server. If you don’t know any better, use Google’s public DNS server,

There is no need to change options [F] or [G], but do select:

[H] Change hostname — enter a hostname for the Spectranet-enabled machine. It doesn’t really matter what you enter here — it’s mostly useful just to replace the junk default name so you can see what you’ve entered for the other settings.

Your screen should now look something like this:

Current configuration
Use DHCP         : No
IP address       :
Netmask          :
Default gateway  :
Primary DNS      :
Secondary DNS    :
Hardware address : FF:FF:FF:FF:FF:FF
Hostname         : fuse

If everything looks correct, select [I] Save changes and exit (you’ll see a brief “Saving configuration...” message) followed by [E] Exit, at which point you’ll be returned to BASIC.

Now type the following commands:


Which will show the standard 0 OK, 0:1 at the bottom of the screen.

Reset the Spectrum again and you’ll see the same four line status display, but this time with your IP address on the last line.

Congratulations! You have now installed the Spectranet firmware. To save having to go through all that every time you start Fuse, save a .szx snapshot at this point, and load that in every time you want to use the Spectranet.


Wiki: Home

Get latest updates about Open Source Projects, Conferences and News.

Sign up for the SourceForge newsletter:

No, thanks