jetsetdanny

A big THANKS and hats off to Andy (Spider) for fixing the site! He did it all by himself, both providing the upgraded software and performing the update. It feels good to be back. Thanks again, Andy! 👍 🙏  👏 🍾

A few weeks ago Richard Hallas brought to my attention a JSW remake that was missing from the lists of games on JSW Central. It is called "Jet Set II" and it was created by Stewart Fordyce (Wizard Software) back in 1985.
I believe this remake remained obscure until October 2022, when it was added to ZXDB and posted on Spectrum Computing by R-Tape. In fact, Richard had spotted it on SC before he let me know about it.
"Jet Set II" has the same layout as the original JSW. Several rooms are completely modified - most notably, "THE FURNACE" (10) replaces "The Front Door", "JUMP IN THE MOTOR" (40) substitutes for "Dr Jones will never believe this", "Space   Invaders" (55) replaces "West Bedroom" and "Above the West Bedroom" (57) bears no resemblance to its original version despite sharing the same name. While most rooms have been altered to varying degrees, some remain unchanged, such as "On the Roof" [18] and "Master Bedroom" [35], the latter now named "GET OUT YOU CREAP".
Guardian paths and item locations remain unaltered, although some guardian sprites have been modified. The title-screen and in-game music are the same as in the original JSW, while the scrolling title message has been edited.
The player is instructed to "guide Willy around his brand new house", to "collect the objects to get some money in the bank" and then to "get to bed before 12:00 am".
I have now fully 'processed' the game (as per my standards). I played it to as near to completion as was possible, identified critical errors, created a bug-fixed version, played it to completion and RZX-recorded it, created a video of my walkthrough for the JSW Central YouTube channel and added the game to the list of games on JSW Central, creating an individual page for it, along with a complete screenshot gallery and download options.
The game's JSW Central page is here, and the YouTube video of my walkthrough is here.
The game as created by Stewart Fordyce was impossible to complete due to a critical bug in the room "Under the Drive" (45). It was impossible to jump over the magenta guardian after entering the room at the upper right, which resulted in Willy's repeated deaths. Since this is the only way out after passing through "Tree Root" (46), where two items need to be collected, this bug effectively made it impossible to collect these items and continue the gameplay, rendering the game incompletable.
An additional problem was that even with this issue corrected, the game would still only be bed-completable, as the wall in the middle of the Bathroom would prevent Willy from finalising the toilet run.
I fixed the "Under the Drive" problem by removing one Earth cell, which prevented Willy from making the same kind of jump over the guardian as in the original "Jet Set Willy". I also solved the Bathroom problem by adding some extra code which allows Willy to pass through the wall during the toilet run. The bug-fixed version can be downloaded from the game's JSW Central page. I was able to complete it, with the loss of one life, at 7:56 in-game time (just like in the original JSW, a life has to be sacrificed to collect the leftmost item in "Conservatory Roof" [43]).
All in all, I would definitely not call "Jet Set II" a quality release by today's standards. I even wondered whether to include it in the "New games" category or rather the "Advanced modifications of the original JSW" section. Finally, I opted for the former. I do think "Jet Set II" has historical value, going all the way back to the "real hardware" era. And, if someone wants to spend an hour or two roaming around Willy's somewhat modified mansion - it's always a pleasure, and it's free, too 🙂 .
If anyone has any more info about Stewart Fordyce or the game itself, please let me know about it (here or by e-mail) and I will be happy to update the information on JSW Central.

A few weeks ago Richard Hallas brought to my attention a JSW remake that was missing from the lists of games on JSW Central. It is called "Jet Set II" and it was created by Stewart Fordyce (Wizard Software) back in 1985.
I believe this remake remained obscure until October 2022, when it was added to ZXDB and posted on Spectrum Computing by R-Tape. In fact, Richard had spotted it on SC before he let me know about it.
"Jet Set II" has the same layout as the original JSW. Several rooms are completely modified - most notably, "THE FURNACE" (10) replaces "The Front Door", "JUMP IN THE MOTOR" (40) substitutes for "Dr Jones will never believe this", "Space   Invaders" (55) replaces "West Bedroom" and "Above the West Bedroom" (57) bears no resemblance to its original version despite sharing the same name. While most rooms have been altered to varying degrees, some remain unchanged, such as "On the Roof" [18] and "Master Bedroom" [35], the latter now named "GET OUT YOU CREAP".
Guardian paths and item locations remain unaltered, although some guardian sprites have been modified. The title-screen and in-game music are the same as in the original JSW, while the scrolling title message has been edited.
The player is instructed to "guide Willy around his brand new house", to "collect the objects to get some money in the bank" and then to "get to bed before 12:00 am".
I have now fully 'processed' the game (as per my standards). I played it to as near to completion as was possible, identified critical errors, created a bug-fixed version, played it to completion and RZX-recorded it, created a video of my walkthrough for the JSW Central YouTube channel and added the game to the list of games on JSW Central, creating an individual page for it, along with a complete screenshot gallery and download options.
The game's JSW Central page is here, and the YouTube video of my walkthrough is here.
The game as created by Stewart Fordyce was impossible to complete due to a critical bug in the room "Under the Drive" (45). It was impossible to jump over the magenta guardian after entering the room at the upper right, which resulted in Willy's repeated deaths. Since this is the only way out after passing through "Tree Root" (46), where two items need to be collected, this bug effectively made it impossible to collect these items and continue the gameplay, rendering the game incompletable.
An additional problem was that even with this issue corrected, the game would still only be bed-completable, as the wall in the middle of the Bathroom would prevent Willy from finalising the toilet run.
I fixed the "Under the Drive" problem by removing one Earth cell, which prevented Willy from making the same kind of jump over the guardian as in the original "Jet Set Willy". I also solved the Bathroom problem by adding some extra code which allows Willy to pass through the wall during the toilet run. The bug-fixed version can be downloaded from the game's JSW Central page. I was able to complete it, with the loss of one life, at 7:56 in-game time (just like in the original JSW, a life has to be sacrificed to collect the leftmost item in "Conservatory Roof" [43]).
All in all, I would definitely not call "Jet Set II" a quality release by today's standards. I even wondered whether to include it in the "New games" category or rather the "Advanced modifications of the original JSW" section. Finally, I opted for the former. I do think "Jet Set II" has historical value, going all the way back to the "real hardware" era. And, if someone wants to spend an hour or two roaming around Willy's somewhat modified mansion - it's always a pleasure, and it's free, too 🙂 .
If anyone has any more info about Stewart Fordyce or the game itself, please let me know about it (here or by e-mail) and I will be happy to update the information on JSW Central.

A big THANKS and hats off to Andy (Spider) for fixing the site! He did it all by himself, both providing the upgraded software and performing the update. It feels good to be back. Thanks again, Andy! 👍 🙏  👏 🍾

Yes, both top hats AND mining helmets!!! 😄

A big THANKS and hats off to Andy (Spider) for fixing the site! He did it all by himself, both providing the upgraded software and performing the update. It feels good to be back. Thanks again, Andy! 👍 🙏  👏 🍾

Yes, both top hats AND mining helmets!!! 😄

I concur - Top hats (or mining helmets) off to Andy!

A big THANKS and hats off to Andy (Spider) for fixing the site! He did it all by himself, both providing the upgraded software and performing the update. It feels good to be back. Thanks again, Andy! 👍 🙏  👏 🍾

Yes you're quite correct sorry.
A few external factors slowed things down a few days sorry. It was suggested to change the temporary message however at that stage it was only a day away from being done.
I did consider posting in the JSW Facebook group but was not sure if an "external site" would be treated kindly, perhaps I was overthinking.
I knew the host was likely to drop legacy php support however (again other reasons) I was not aware exactly when this was to be, as you know they usually give a few weeks notice of "we're dropping xyz at the end next month" , it is quite possible I missed this notice however.
I did toy with the idea of adding a temporary forum (as was done once before) but by the time I'd done that I could of done this.
 
However on a positive note, we are now future proofed for quite a considerable time and if it should happen again ( ! ) something suitable will be posted and linked to.

By comparing Willy's sprite data with the attribute byte values assigned to the various block types in the cavern data, I've discovered a few effects that I think will arise within the Manic Miner game engine.
 
If you have more than 34 remaining lives and if the spare lives on the status bar are set to their rightmost frame of animation.  Willy's back foot in that frame has a byte value of #03, which matches a couple of magenta INK on black PAPER blocks in the game:
- In 'Abandoned Uranium Workings', some of the errant blocks (in 'even' columns) across the middle of the cavern will act as conveyor cells (no animation, but they will drag Willy rightwards).  This effect could be quite erratic if the in-game music is left on, meaning that the spare lives pass through that animation frame and the conveyor effect periodically stops and starts.  This should affect the new platform directly underneath the cavern's sole crumbly platform - that is in fact the very same new platform which led @DigitalDuck to improve his score here, which gave rise to this discussion!  N.B. No POKE is needed to observe this effect - just set the remaining lives to the appropriate frame;
- In 'Return of the Alien Kong Beast', the mid-height Water cell platform patrolled by the right-most 'rolling rock' guardian will, in theory, become crumbly.  Unfortunately, Willy can't access that part of the cavern to stand on that platform and cause its pixels to crumble away, because of the aforementioned blockage on the left-hand side of the cavern (as pointed out by DigitalDuck).  There is a single-cell platform occupying the same character row towards the left of the cavern (just below/to the right of the leftmost banana item), which is reachable during game play, but unfortunately that block sits in an 'odd' column, so the overwritten attribute (corresponding to a different part of Willy's sprite) doesn't match the crumbly cell attribute, and so no crumbling of pixels will occur if Willy stands on it even if it has been corrupted by a rogue attribute.  However, if that platform were extended by one more block (either left or right will do the trick), then the new extension to that platform would crumble when stood upon: POKE #DD02,#43 or POKE #DD04,#43 (in decimal: POKE 56578,67 or POKE 56580,67) - apply before entering the cavern.
 
Meanwhile, if you have 36 or more remaining lives and if the spare lives on the status bar are set to either their second or third frame of animation, then I believe the attribute value #06 (corresponding to the next pixel-row up in Willy's sprite) will be written across alternate cells of the top character row of the caverns.  This could also have gameplay consequences:
- The value #06 is assigned in 'The Menagerie' to an (unused) Fire cell type (the yellow bush that is encountered in other caverns), so as the number of extra lives continue to tally up, the top three items will be either embedded in or sandwiched between Fire cells, making them uncollectable without being killed (unless you move the animation of the remaining lives on to the first or last frame);
- Similarly, 'Processing Plant' would be incompletable once the errant Fire blocks reach across to the portal (and probably before that - I don't think it's safe to drop down from the starting point in the cavern without first making a jump that means Willy's head passes through the top character row);
- And the route options in 'The Warehouse' would be more restricted (for instance, you couldn't jump over the first Fire cell to Willy's right upon entering the cavern, without hitting one of the newly-created overhead Fire cells).
 
P.S. Whilst researching this post, I discovered for the first time that Matthew's original design for 'The Sixteenth Cavern' may have incorporated a switch!? (The switch graphic from the Kong caverns is present, unused, in the 16th cavern data.)

Just for fun: if you collect the bottom item in Skylab Landing Bay while you're on 33 lives and *99xx points, you're killed by the extra life you're awarded for collecting the item.
MM-extralife_VP8.webm

If you notice anything amiss please do a hard refresh in your browser (typically CTRL+F5 or CTRL+R) or hold down the shift key and click the refresh button.

We have updated the software here to future proof the site for newer server requirements.
Sorry for the downtime however it was immediately necessary without prior notice, otherwise an announcement would of been shown for a few days.
 
You'll find things almost just as they were, we decided to remove the redundant 'articles' system as no one ever used it. The topics are best placed if needed with a new area for guides and tutorials.
 
Note that there are still some small adjustments to make over the following week however the site is ready to be opened again.
 
Of course if you should spot anything amiss please either post here into this topic or message me or jetsetdanny.
 
Thank you.

Is there a precendent set any in any other mods of JSW whereby just for decorative purposes for example
items or platforms have been  put in inaccessible areas, tempting players to think 'How do I get to there?'
when really it has been impossible?

Thank you for your thoughts. I believe the answer is 'no' to both questions.
I've checked the rooms in question in JSWED, changing the attributes of all cells to certain default colours I always use for these occasions (blue on blue for Earth, green on green for Water, etc.), which rules out any hidden platforms.
I also checked the guardians. I believe there are no switches in the game. I am pretty sure there aren't any custom code modifications, either - my understanding is that the game was designed using JSWED's GUI without any 'fancy' stuff.

Thank you for your thoughts. I believe the answer is 'no' to both questions.
I've checked the rooms in question in JSWED, changing the attributes of all cells to certain default colours I always use for these occasions (blue on blue for Earth, green on green for Water, etc.), which rules out any hidden platforms.
I also checked the guardians. I believe there are no switches in the game. I am pretty sure there aren't any custom code modifications, either - my understanding is that the game was designed using JSWED's GUI without any 'fancy' stuff.

I just tried the above experiment. (The idea behind it being to match the crumbly attribute in Eugene's Lair to one of the bit maps for a part of Willy's sprite.) 
When Willy stands on the corrupted conveyor, the conveyor's pixels start to crumble downwards whilst they're also animating rightwards! It's more interesting if you proceed along the conveyor from right to left, rather than vice versa. (So the pixels keep on coming from the left, otherwise they all disappear quite quickly.)
Also, try leaving the music on with the spare lives dancing - the errant blocks change colour in time with the music, and if Willy is standing on the right hand end of the conveyor, then the downwards crumbly-conveyor animation keeps stopping and starting depending on the animation frame of the spare lives!
(A couple of other observations: the conveyor no longer drags Willy along, even though it is still animated to look like it should. And the ever head stalactite is no longer lethal to Willy.)

So I have a couple of corrections to this, namely that I'd missed some things that reduce the life count before some levels become incompletable:
Eugene's Lair - at 39 lives, the platform with the black toilet is completely overshadowed by the garbage platform. Unfortunately it's now one cell too high to safely drop down from, and there's no other way down without falling too far.
Return of the Alien Kong Beast - at 37 lives, all ways back down are blocked, and again the only way to get down is to fall too far.
Attack of the Mutant Telephones - while it's possible to go from top to bottom by jumping through the top of the screen, the platform in the middle becomes an island once you reach 42 lives and there's no way to get up or down from it.
 
Interesting. I'll post about it in that thread if I decide to experiment with that, but it's definitely unique for JSW-style games.

I suppose there is an ecological analogy to be drawn - overpopulation of some species (not generally turtles though!) can be damaging to the ecosystem once natural predators of those species are eliminated from a habitat.

"Terry The Turtle" is the game to try it "the natural way", i.e. without any POKEs.
You start out with 7 lives which are visible on the screen. As you gain extra lives, 4 more become visible as little turtles on the screen, just like the original 7. The next 3 extra lives are not marked in any visible way, and then with the 15th life the leftmost little turtle at the bottom of the screen, symbolising a life, starts to flicker. Then, with the following extra lives, the next turtles at the bottom of the screen start to flicker. When the number of lives exceeds 28, it affects the display of the room names (the letters disappear starting with the leftmost one; the effect is irreversible - even if the number of your lives goes down below 28 again, the affected letters in room names in new rooms you enter are not visible). With even more lives the game is slowed down or it can crash or become unplayable in some other way (e.g. because of 'rogue' cells blocking your way).
As the author of the game, Steve Dixon (Jammajup), explains, "if you are good at these types of games and constantly use the emulator save state you can collect so many lives you can slow down or even crash the game!" Indeed, this is a serious problem and in order to eliminate it, while recording the RZX walkthroughs of the four versions of the game (three of which still need to be improved - please see this thread for details), I deliberately killed Terry many times during each walkthrough, so as not to have more than 28 lives at any point in the game. The elimination of the excessive number of lives had to take place, much as I dislike serial suicides 😉 . However, if someone is interested, you could experiment with the extra lives and the effects their excess produces.
 

Sendy's "Manic Person" has the stack address changed (in both versions). It uses the spare bytes related to unused guardian data at #FAF3 - #FAFF. To be precise, the instruction at #8401 - #8403 places the stack at #FAFE. So when there's one address on the stack, it occupies the last two bytes of this spare space (i.e. #FAFE and #FAFF). I don't quite understand why it works this way, but then the following addresses are occupied going 'backwards' (i.e. the next occupied pair of addresses will be #FAFC - #FAFD, then #FAFA - #FAFB and so on). 
When working on the 'postproduction' of "Manic Person" (adding some special effects and loads of music), I was a little worried that a stack overwflow could occur, since the available space allocated to the stack is limited. However, after playtesting the game by completing it twice (two sets of caverns), there were still four or six spare bytes in the allocated space (00s, not overwritten by the program). It was actually the same amount as after completing the game for the first time (one set of caverns). So I decided it was safe to leave the stack there, as I couldn't think of any scenario in which it would occupy (overwrite) more space.
The change was done in order to use the space at #934C - #9CFF for other purposes, of course.

It sounds like Invalid Arrows are exactly what you're looking for.

Actually, you're right. In Jet Set Willy, the stack starts at the bottom of page #5B of memory (that page was originally designated as a printer buffer for use if your ZX Spectrum is hooked up to a ZX Printer, if I recall correctly? - which is obviously not a consideration when playing games like JSW/MM, so it's a good place to put the stack.)
I had assumed that this was also the case in Manic Miner - that the base of the stack would be placed at #5BFE-5BFF.  And hence at theoretical risk of eventually being overwritten by the bonus lives (if enough of them built up?  The errant blocks would have to be reaching the bottom right of the playing area for that to occur, so other things are likely to have gone catastrophically wrong long before that occurs!)
But apparently it's not even a theoretical consideration, because according to SkoolKid's MM disassembly, the base of the stack is near the end of the remnant source code which starts at #934C.  So the stack builds up from addresses #9CFE-9CFF.
(Incidentally, anyone working on a MM mod and finding a purpose for that available part of memory - #934C-9CFF - would be advised to steer clear of the last few bytes, lest the program overwrite the addresses stored on the stack during flow of execution, or vice versa!) 

Ah, that item you're referring to is in an 'odd' column number, so nothing is printed there for a Willy sprite in its leftmost frame of animation. (Well, technically the value #00 is written there, but that's what was already there anyway as it's an air cell in a room with a black background, so nothing changes in that cell and the item remains collectable. Try setting the dancing lives to a different animation frame and I think you'll find that it's uncollectable.)
Conversely, the auto-collected item in Kong Beast is in an 'even' column, and it's actually one of the spare Willy's front foot which 'collects' it - the byte value for his feet in that position is #77, the first 7 represents his back foot, the second digit is his front foot, and that 7 is interpreted as white INK in the attribute buffer!