Cheat modes in JSW128

[Spider]

It was something also on my "todo" list at some point although I highly suspect Danny will beat me to it given my schedule of late. :)

[IRF]

I left a big clue in post 17 of this thread. ;)

[Spider]

I left a big clue in post 17 of this thread. ;)

And the big hand should be pointed at ;) , if I am on the right track. But it will have to await a bit. :)

[jetsetdanny]

I just found this thread. How amusing!

 

It's good to see you around, John :).

 

So what exactly is amusing about this thread?

[JohnElliott]

I get to see people studying my work. And, tbh, I'm amazed the details of the cheat mode haven't been common knowledge for years, considering how long JSW128's been out there.

[jetsetdanny]

Your work has had an enormous influence on this scene and has been the cornerstone of many a fine project :).

 

The period of the Dark Ages will soon be over. As Ian mentioned, I intend to crack the mystery once

[Spider]

I'd take a wild guess perhaps people were not looking for one ? , Well maybe!

 

Although a completely different "kettle o fish" that huge PC based multi-JSW/MM game that C.Rothwell released in about 96ish, that had a cheat mode too but it was very difficult to figure out or find despite clues. I do recall getting it to work once many moons ago.

 

Good to see you here John! :) :)

[IRF]

Your work has had an enormous influence on this scene and has been the cornerstone of many a fine project :).

 

The period of the Dark Ages will soon be over. As Ian mentioned, I intend to crack the mystery once

[IRF]

There is a potential flaw in the JSW128 game engine (or at least in John Elliott's explanatory notes for the engine).

 

Whilst the original guardian class table (#A000-#A3FF) provides a #FF Terminator byte at the address #A3F8, if you create further guardian class tables then another #FF Terminator byte needs to be inserted at the start of the final 8-byte entry of the additional tables.  e.g. - If you create an additional guardian class table across pages #D8-DB of memory, then an #FF value needs to be inserted at address #DBF8.

 

If you don't do that, and if the first entry of the additional table has a defined guardian (i.e. of Class #00), then there is a risk that the code which populates the guardian buffer (#8922-#8949) will cause errant Class #00 guardians to appear in any room* that uses the additional guardian class table, with potentially disastrous consequences!

 

(*Unless said room has a full complement of eight guardians, or unless the structure 'FF 00 FF 00 FF 00 etc' is used to terminate a less-populated room's guardian list, instead of 'FF 00 00 00 00 00 etc'.)

 

The explanatory notes for the JSW128 game engine should alert the game designer of the need to include a #FF Terminator byte at the start of the last slot in every guardian table (unless the editor could be made to automatically insert the Terminator byte whenever a new guardian table is created).

 

**

 

EDIT: A similar bug afflicts the Softricks Edition of JSW - for the same reason, there should be an #FF byte at address #A7F8 (corresponding to the start of the last entry in the double-length guardian class table in the Softricks engine), but it seems that there isn't.

 

 

**

 

FURTHER EDIT: There is also a glitch in JSWED, whereby if a room has a full complement of eight guardians, and if you delete one of them in JSWED's GUI [other than the last one in the list] and then navigate away from that room in the GUI before replacing the guardian that you've just deleted, then a guardian of class #00 (if guardian class #00 has been defined) appears at the left-hand side of the room when you play the game, due to the failure of JSWED to write a 'Terminator' byte into the guardian list for that room.

 

I guess what happens is that, in general, when you delete a guardian from an early slot in the guardian instance list (guardians are listed as pairs of values in Offsets #F0-#FF in the room definition), then the later entries get shuffled up to fill the gap.  If there were fewer than eight guardians then there will be an #FF Terminator byte at one of the even addresses in the range of Offsets #F0-#FF, and it will gets shuffled up as well.  But if there were a full complement of eight guardians prior to the deletion of one of them, then seemingly Offsets #FE-FF for the room are just NOPped out, and this is interpreted as an instance of Guardian Class #00 in the room (with a horizontal coordinate of 00).

Edited March 9, 2020 by IRF

[RuffledBricks]

On 2/2/2020 at 1:02 AM, jetsetdanny said:

The Writetyper cheat is activated at the bottom of "First Landing" (028), just like in the original "JSW", by keying in the word "writetyper".

 

A foot appears to the right of the last remaining life to show that Writytyper has been turned on.

 

The cheat uses keys 1-8 (instead of 1-6 in the original "JSW") which need to be pressed together with 9 to teleport to another room.

Out of curiosity, did anyone ever make a list of the room codes for Writetyper in JSW128?