Copy Protection in 'Jet Set Willy': developing methodology for retrogame archaeology

[Metalmickey]

You could buy your own mansion, with a stern housekeeper and a crazy chef...

maybe i could invent a machine to make seven copies of myself and practise jumping over a giant possessed moving saw  :wacko:

[jetsetdanny]

I have just tried to load an unmodified "JSW 2" using the colour code protection sheet from here and I don't seem to be able to do it. I input what I believe is correct values and nothing happens. Has anyone come across this problem before?

[Spider]

On 6/27/2024 at 7:29 PM, jetsetdanny said:

I input what I believe is correct values and nothing happens. Has anyone come across this problem before?

No, it is normally reliable.

Are you 100% you entered the correct code ?

This might sound odd but try it again, if it persists, when on the code entry page itself being asked for a code, what is the byte value at 24965 ? It should be 2

The instruction itself is at 24964...

24964 JR NZ , 24968 ; jump if the code is wrong to ask again (or crash if its the second wrong attempt)

If 24965 = 0  it reads like this

24964: JR NZ, 24966 ; jump if the code is wrong to accept it anyway:

24966: POP HL ; throw away the current return address from the stack

24967 RET ; Now the next one one will take us to the Title screen

Enter something other than the correct code aka 1246 or 1111 etc

 

Random: I think the codesheet for the AMS version is different (colouring aside) but I've not actually compared them, never saw the need.

[jetsetdanny]

Could someone please RZX-record (preferably using SPIN, but perhaps any compatible emulator would do) the loading sequence of JSWII? So that the person watching it would see the person who loaded the game "go through" the colour code?

I would need this sequence for an improved video of both the walkthrough and speedrun of "JSWII" for the JSW Central YouTube channel. Any help would be appreciated!

[Spider]

I recorded it in Spectaculator. This does not play back in Spin. Can redo if needed. I set Spectaculator on flash load , using the 48K model and just recorded the whole lot to the title screen.

Its the original tape not the re-release*** so it asks for a code which I provided (yes the correct one, the code was not modified)

jsw2_spectac.rzx

 

I re-did this in Spin , its the whole lot , but you can save as video and trim down. It did not speed up loading for some reason with this emulator. Note I had to record this in 128K (Sinclair toastrack model) because my Spin 48K rom is quite modified whereas the 128K one is not.

jsw2_spin.rzx

Please say if anything needs redoing. Note I failed the first key entry, my fault.

 

*** Re-release, its quite different. The original should be one short piece of Basic containing the loader then a large headerless block, nothing else. The re-release tends to be about 3 pieces of code to 'bypass' the keycode. Best I can remember with this version (re-release) without having looked into it in details for many years is its a snapshot in effect of the game at the title screen. This was -not- used here for the above, only the original tape. complete with seven pages of keycodes! 🙂

 

[jetsetdanny]

Thanks, Andy, I believe the Spectaculator recording will do for my purpose! 👍 In that one, you did *not* fail any keys as far as I can see, right?

[Spider]

6 hours ago, jetsetdanny said:

Thanks, Andy, I believe the Spectaculator recording will do for my purpose! 👍 In that one, you did *not* fail any keys as far as I can see, right?

That's correct, first time pass. 🙂 

C1 + Page 2 = R/Y/R/Y , 2/6/2/6

[Norman Sword]

Most pictures I have seen of the code sheet are blurred. This copy whilst not a photgraph or a scan of the original, is far clearer. No idea who can get the credit for setting out these graphics.

[jetsetdanny]

Thanks, Norman Sword! 👍

[Jet Set Willie]

I just found this topic, otherwise I would have asked metalmickey to share us some photos of his mansion, so we could see if it´s anything like in JSW. But a photo or two from mineshaft will do, if you didn´t make it. 😉

Some colours from the colour code sheet and password screen didn´t match with the original MSX tape. I don´t mean that there´s an error in some parts of the sheet, as by typing in "wrong" colours the password screen let me play the game. The colours and numbers on password screen may have been in wrong order, I think.

Thank you Norman for the sheet, mine was similar as what Andy posted above your post. And thank you Danny for the link! 🙂