Running Turbo Pascal 1.0 on (a real) Spectrum +3

As I wrote in my previous post, I was determined to run Turbo Pascal 1.0 on a (real) Spectrum +3. The issue is how to dump a DSK image file (on the PC) onto an actual three-inch Amstrad/Sinclair floppy disk (like the one shown in the second picture by a friend of mine who, by the way, is a very skilled hacker).

One obvious way is to connect a three-inch floppy drive to a modern PC. While this should work, I've already tried and failed :-(
Moreover, in doing so I was always worrying about damaging the floppy drive, the PC or both. For these reasons, I was looking for an "all software" solution.

Luckily, I've found a very nice utility in the Alchemist Software PD/Shareware Library allowing to backup (and then restore) disks to tapes. Basically, this utility dumps the disk tracks to a series of data files. Each disk (actually, each side of a disk) is dumped into five 36K blocks, which is hardly surprising considering we need to dump 180K and the available RAM is about 40K. Curiously, this neat utility cannot be found in the Utils section. To obtain this utility you need to download the game Cannon Bubble +3, from the Games section. While it is indeed a good game, we're not interested in the game per se, but rather in the bundled utility.

Using this utility in Spectaculator it's easy to create a (virtual tape) TZX file containing the dump of any DSK image file. In my test I used the Turbo Pascal image file I've previously created.

I thought (hoped) to bring this TZX into a real Speccy using an SD card and the ZXMMC+ interface. This would have been amazingly fast and cool ;) ... unfortunately, my plan have failed because I haven't figured out how to use the ResiDOS, needed to load the virtual tape stored in the SD card, and the +3 floppy drive (when the ResiDOS is active the drive identifiers are mapped to the SD card slots). I think there must be some workaround, but I haven't found it out yet.

So, how did I manage to dump the disk? Well, in the old-fashioned, simple and painfully slow way of using the EAR socket of the Speccy (as you might remember, it takes about five minutes to load a 48K game and we need to dump 180K... you do the math!). What I did is equivalent to dumping the DSK image into a real tape and then load it into the Speccy... but without the real tape ;)

I've connected the Speccy to the soundcard of my PC and I've used the tape recorder of Spectaculator to play the just-created virtual tape. If you try this way, make sure to select "Boost loading noise volume" in the options for the Cassette Recorder (Main menu -> Options... -> Cassette Recorder).

While I'm not totally satisfied because the way I had to fall back on the soundcard-based solution, it indeed worked :-) as the third picture shows.