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(Atari ST) PoP saved game editor

Posted: December 4th, 2017, 6:54 pm
by rockyone
For Atari:
Image

Re: POP1 (w/ level editor, cheater, save game editor) & POP2

Posted: December 4th, 2017, 8:24 pm
by Norbert
rockyone wrote: December 4th, 2017, 6:54 pm For Atari:
Image
Hi rockyone, thanks for posting the screenshot.
Do you have a download link for your program?
Is it open source? Which year did you create it?

David, maybe split this thread in two?

Re: POP1 (w/ level editor, cheater, save game editor) & POP2

Posted: December 4th, 2017, 9:17 pm
by rockyone
I think I did it in the 80s and changed a bit later (but I do not know why!)
My children had the game but the floppy was unfortunately destroyed.
So I reinstalled this small PRG on a version taken on the internet.
The loading of this version is long .. Wait

Everything in this folder http://www.mirari.fr/file/browse?f=714&u=506

Re: POP1 (w/ level editor, cheater, save game editor) & POP2

Posted: December 5th, 2017, 7:57 pm
by Norbert
Thanks.
Is it okay if I add the program to popot.org?

Re: POP1 (w/ level editor, cheater, save game editor) & POP2

Posted: December 6th, 2017, 9:16 am
by rockyone
you can, but thank you kindly leave the source on mirari.fr.
Test that it works again ... me, long ago that I have more joystick ..
The levels of this game have a specific name?

Re: POP1 (w/ level editor, cheater, save game editor) & POP2

Posted: December 6th, 2017, 12:32 pm
by Norbert
Any reason why you only want the Omikron BASIC source (PRINCE.BAS) distributed from one website (mirari.fr)?

Re: POP1 (w/ level editor, cheater, save game editor) & POP2

Posted: December 6th, 2017, 12:40 pm
by rockyone
I think to change the interface, but no specific date.
This is the reason for my question in the previous post.
Do the levels of the game have a name ??
But if you stick to it, do it !

Re: POP1 (w/ level editor, cheater, save game editor) & POP2

Posted: December 6th, 2017, 12:45 pm
by rockyone
Have you tested that it works?

Re: POP1 (w/ level editor, cheater, save game editor) & POP2

Posted: December 6th, 2017, 12:56 pm
by Norbert
rockyone wrote: December 6th, 2017, 12:40 pmDo the levels of the game have a name ??
Yes, for the original names see the Apple II column here:
viewtopic.php?t=3364

Re: POP1 (w/ level editor, cheater, save game editor) & POP2

Posted: December 6th, 2017, 1:14 pm
by rockyone
Thank you
I would do the image with the names and numbers of the levels.
I have a young neighbor addicted to video games, I ask him to lend me a joystick to check ...
next year...

Re: POP1 (w/ level editor, cheater, save game editor) & POP2

Posted: December 6th, 2017, 1:25 pm
by Norbert
Sounds good. :)

Re: (Atari ST) PoP saved game editor

Posted: December 8th, 2017, 9:38 pm
by David
Norbert wrote: December 4th, 2017, 8:24 pm David, maybe split this thread in two?
Done.
rockyone wrote: December 4th, 2017, 9:17 pm Everything in this folder http://www.mirari.fr/file/browse?f=714&u=506
I tried the disk image from "Prince Of Persia + Loader.zip" in the STeem emulator.
So, I see this is a tool to start PoP (Atari ST version) on any level with any number of hitpoints.
I can't change the remaining time. Is this intended?
To load the edited savegame, press Ctrl+L on the title screen of the game.
Important: PoP works only with TOS version 1.02, and not with version 2.06. I learnt this the hard way...

Re: (Atari ST) PoP saved game editor

Posted: December 9th, 2017, 9:45 pm
by rockyone
David wrote: December 8th, 2017, 9:38 pm I can't change the remaining time. Is this intended?
I do not know if the remaining time is saved in the "Prince.sav" file.
But currently it can not be changed

Re: (Atari ST) PoP saved game editor

Posted: December 10th, 2017, 1:01 am
by rockyone
I just checked, the time is well recorded.
But $0 = 60 minutes, $F1 = 0 seconds!

Re: (Atari ST) PoP saved game editor

Posted: December 14th, 2017, 8:31 pm
by David
I looked into the PRINCE.SAV file.
* Offsets $00-$01 store the time. See below how.
* Offset $02 stores the level number.
* Offset $03 stores the number of hitpoints.
* Offsets $04-$0E store zeroes, except for offset $06 that stores $02.

On your disk image, PRINCE.SAV begins at offset $C6000.

About the time:
This version of the game stores the *elapsed* time.
It's stored on two bytes, in *little* endian byte order. This is odd, because the M68k CPU in the Atari ST uses big endian byte order.

The unit of the time is frames: 725 frames = 1 minute, 12 frames = 1 second.
(Yes, the numbers don't match exactly: 725 = 12*60+5)
By the way, this matches the timer in the original PoP for the Apple II: https://github.com/jmechner/Prince-of-P ... IALK.S#L68

Examples:
$0000..$02D4 will show as 60 minutes left.
$02D5..$05A9 will show as 59 minutes left.
$05AA..$087E will show as 58 minutes left.
...
$A9C3..$A9CE will show as 3 seconds left.
$A9CF..$A9DA will show as 2 seconds left.
$A9DB and anything above will show as 0 seconds. It seems there is no "1 second left" message.
($A9DB = 43483 = 59*725+59*12)