Completable tape version of the original edition of "Jet Set Willy: The Continuing Adventures"

"Jet Set Willy: The Continuing Adventures" is a 1985 game by Adam Britton. It was created using Paul Rhodes' "JetSet Editor".

In the mid-1990s, the game was recovered from the original tape and transferred to emulator format by Richard Hallas. It was released in November/December 1995 as part of the snapshot pack in Issue 3 of the "Emulate!" online magazine. The original edition of the game was not completable due to a critical bug, discussed by Andrew Broad on his website, the archival version of which can be found here.

In April 1998, Adam Britton released The Special Edition of the game, completable, with new rooms and various other improvements.

However, an 'official' bugfixed version of the original edition has never been released. It could be argued whether or not there is any need for it, as a completable Special Edition is available. Andrew Broad argues that he considers TCA and TCA-SE to be parallel variants, since TCA-SE removes "The Sky-Ladder" (42), and also because of the historical value of the original TCA. It could be added that there are some differences in gameplay, e.g. in the rooms "The Further Recesses" (49) and "Don't Fall Off!" (58), which make playing the original and the Special Edition a slightly different experience.

This download offers a bugfixed, original edition of "JSW: The Continuing Adventures" in TAP and TZX format, prepared using the SNA snapshot from the "Emulate!" online magazine, dated 21 September 1995, and converted to tape format in a way which aims to reflect the original loading process.

It should be noted that other versions of the original edition of "JSW: The Continuing Adventures" are available on the internet. A SNA file dated 19 January 1997 is hosted on JSW remakes. A Z80 snapshot dated 20 December 2004 is hosted on World of Spectrum and Spectrum Computing. These files contain the so-called Bad Pause-Bug Fix (please see Andrew Broad's explanation for details). The Bad Pause-Bug Fix must have been added to the game file some time *after* it was released as part of the snapshot pack of the "Emulate!" online magazine. It does not affect this particular game, since Room 63 is not edited or used during gameplay. However, the code in these snapshot files at #8B07 - #8B09 and #FFF0 - #FFFF is different from the code in Adam Britton's original file.
 
The following changes from the "Emulate!" magazine SNA file have been made in the #8000 - #FFFF range:

1. The fix suggested by Andrew Broad was applied to make the game completable. A Water cell was added at (6,23) in "The Miniature Sherwood Forest!" (17) by changing the value of the address #D135 to #01. This makes it possible for the player to collect a previously unreachable item there. This change has also been applied by Adam Britton himself in the Special Edition of the game.

2. The Empty Room Screen Buffer at #8000 - #80FF and the Empty Room Guardian Buffer at #8100 - #813F have been NOPped out (with the value #FF at #8140 terminating the buffer). This change was done for the sake of the 'elegance' of the tape file, as a game loaded from tape should not have any values there other than zeroes before the initial room and its guardians are loaded into the buffers.

3. The following variables: the current room number (#8420), the number of lives remaining (#85CC), Willy's y-coordinate (#85CF), Willy's animation frame (#85D2), the address of Willy's location in the attribute buffer at #5C00 (#85D3 and #85D4), the Rope status indicator (#85D6), 256 minus the number of items remaining (#85DE), the Music flags (#85E2) and the Temporary variable (#85E4) have been NOPped out, for the same reason of 'elegance'. These variables are initiated when the game starts, so they should have a value of #00 right after the game has been loaded from tape. A visible (or rather audible) effect of this is that the in-game music is turned on by default when the game is started (contrary to what happens in the SNA snapshot, where it is turned off).

4. A custom BASIC loader was created, based on the original one, with some modifications. The loading process reflects Adam Britton's original solution to the loading screen, which is a block of compressed code loaded and then decompressed to display the picture it contains on the screen while the rest of the game loads. Three POKEs which allowed the player to bypass the colour code protection from the original "Jet Set Willy" were removed from the loader, as this bypass is already present in the game code. A short pause was introduced after the loading screen has been displayed to make it visible to people who use fast loading on emulators. It should be noted that when Adam Britton created the Special Edition of the game, he did not bother to compress the loading screen (it loads as a standard SCREEN$ code block 6912 bytes in length, as opposed to 2728 bytes of compressed code in the attached tape files). So this version restores a solution from TCA 'lost' in TCA-SE.

As a result of the changes described above, the player is offered a completable version of Adam Britton's historic game in a choice of two tape formats, preserving the original 'loading flavour'. The game can be completed with one life lost - it has to be sacrificed to collect the leftmost item in the room "The Miniature Sherwood Forest!" (17). While not really elegant (it should be possible to complete a JSW game, difficult as it may be, without losing a single life), it is consistent with the original "Jet Set Willy", where even after applying the official Software Projects POKEs to make it completable, one life still has to be sacrificed to collect the leftmost item in "Conservatory Roof" (43). Currently, the best known in-game completion time is 8:23 am (please see the video on the JSW Central YouTube channel).

The SNA snapshot of the game from the "Emulate!" online magazine (JSWCONTA.SNA) is included in the ZIP package offered here for download, for the sake of completeness.

It is possible that one day the file of "JSW: The Continuing Adventures" will be recovered (again) from its original tape and transferred to the TZX format. Another bugfixed edition will then be in order. Until then, please enjoy the restored and fixed file included in this ZIP package.
 
John Elliott's JSWED v. 2.3.7, Andrew Broad's SPECSAISIE 1.3 Beta 5 (the latest publicly available version is v. 1.2) and Claus Jahn's ZX-Blockeditor v. 2.4.3 (a newer version 2.4.3.1 is available were used to prepare this bugfixed version of "JSW: The Continuing Adventures". Richard Dymond (SkoolKid)'s complete JSW disassembly (available in hexadecimal and in decimal) was also very helpful in this endeavour.

The game's page on JSW Central is here.