Demozoo hacking job(s)

Hacking?

When I say ‘hacking’, it’s used purely as an overall description of what I’ve been doing to help out with DemoZoo’s Atari ST side of things.

Some of the releases were only available on certain compact disk (note disk, not disc as in CD-ROMs) groups’ releases. These were one or two floppy disks and contained as much as possible due to the usage of file packers for both executable and data files.

Demozoo prefers to have each release as part of a single download per demo/intro. With links to YouTube videos if they’re available.

This is where I come in and (try to) help. Not every attempt is a successful one, mainly due to me being able to remember everything that I can about similar tricks from 25-30 years ago.

On the Syndicate Delicious Disk 67 was the “Syndicate FettisDag Slideshow”. Lotek, from Demozoo, asked if it was possible to separate out the demo (Option 4 on the disk menu) and accompanying files into a separate .ZIP file.

So I took on the challenge. This blog post is an example of this kind of task that I did last week where it had a successful outcome.

The target’s files

After working out what files belonged to the demo and copying to a working folder, the examination started.

There was a LOADER.PRG, several PI1 (Degas art package) files and a separate FLURP.PRG (the main demo). At first glance none of the PI1 files had the usual file lengths of either 32034 or 32066 bytes. So I assumed that there was some kind of file packing involved.

Running the demo directly, not via the loader, proved this as correct. All the graphics in the slideshow were corrupted. So this pointed to the loader being a Trap #1 depacked type.

A what kind of loader?

These loaders would hook into the TOS file loading routine. When the target program issued a FOPEN ($3F) command, the loader would:

  1. Open the file
  2. See if the files was packed with the packer(s) the loader recognises
  3. Depack the file if it is
  4. Hand control back to the original program

As this was a slideshow, this would happen with each PI1 file used by the demo.

Initial Steps

So my first step was to open the LOADER.PRG using Easyrider 4. Lots of gobbledygook but the tell tale strings showed bits of “AntiBitOS by Illegal”. Damn, it’s been protected by an anti-cracking tool, written by one of the scene’s most well known Atari ST crackers, Illegal of The Replicants.

However, after posting about this setback in the FB group, I remembered that Orion (also of The Replicants) had released a tool called ‘Dec0de’ a few years ago. It comes in ST and command line PC versions and it removes all kinds of cracker-proof envelopes devised by other crackers as well as commercial protection systems too, especially Rob Northern’s. There’s a full list on Orion’s GitHub area.

I ran the loader through the PC version of Dec0de and out popped a deprotected version of it. Loading that new file into Easyrider confirmed my suspicions that it was a Trap #1 loader and that it depacked data files on the fly. We’re getting somewhere now!

Oh, wait a minute, it’s not a known depacker header that the loader is looking for. The norm for most file packers on the Atari ST was to have the first four bytes as a mini header to say “this file was packed with this range of packers”. But in this case, the demo creators have changed the first 4 bytes of each packed file to mask which packer was used. Grumble, grumble …. more blocks in the way.

The loader was disassembled (via Easyrider than through Stew’s excellent Convert tool), into a source code file. I now have to compare this routine against my collection of depack routines I’d collected whilst writing my Multi Depacker tool that I’d coded over 25 years ago.

With luck, the second depacker routine that I looked at was Ice Packer v2.20. It was a near perfect match. So let’s try fixing the file headers of the PI1 files using a hex editor back to “Ice!” and see what happens when I try to unpack them.

This worked well for all but two of the files on the STAX disk 62 release that I was working with. They wouldn’t unpack correctly. So close, but so far.

Luckily Lotek had mentioned that this demo was originally released on Syndicate’s Delicious Disk 67. I found that disk on STonish.net, copied the two problematic files to my working folder, hex edited the header and they depacked first time. Another step towards a win!

The final step involved more hex editing, this time removal of all the A:\ from the front of the filenames. This would (in theory) allow the demo to run from a hard disk.

Once this was done, I cleared all the temporary files and tools out of my working folder and launched the demo. It all worked and none of the images were corrupted at all!

Here are a couple of the screenshots from the demo:

A .ZIP archive was created with this HD version and posted in the private FB group where these requests appear. (I’m not giving the group name out, so don’t ask).

The end result

The demo is now available from Demozoo in its deprotected, HD compatible and unpacked version.

Get your copy from here, or grab yourself the original release from STonish.net.

My ZX Spectrum Next has arrived!

(OK, it arrived 2 weeks ago, but I forgot to add it to this site).

It’s a dream come true – a souped up ZX Spectrum with all the bells and whistles that allows me to access files as and when I want off an SD card.

It’s what I thought the ZX-MMC would do for my +3, but it’s leaps and bounds ahead. I can see the +3 being sold off once we’re all back to normal, whenever that may be.

Whilst I’m working from home due to COVID-19, I can’t give the machine the full attention that I want to do. There are rumours from work that we might be made to go ‘one week on, one week off’. If this does happen, then I’ll be able to give the machine a lot more of the spare time it needs.

My hats off to Phoebus Dokus as the manual is lip-smackingly gorgeous. As a technical author by trade, it makes me go a little green at the gills 🙂 I just need the time to read it and start programming something in NextBASIC, but that will have to wait a bit.

However, using the good old DZ80 disassembler, I’ve already created some infinite lives pokes for two of the commercial games that I bought and working on the others. These will end up on here as tutorials at some point.

More updates on my progress as the spare time allows!

Wading through my back catalogue

After rescuing the content to recreate an old page from one of my original websites that covered Atari ST cartridges, I started going through all of the other bits and pieces that were on my website’s ‘To Do’ cards on Trello. There’s still quite a bit to get through!

New pages

There are now two new “odds and sods” pages: one for the ZX Spectrum and the other for the Nintendo DS. If you’re a teacher or maybe a quiz master, you might want to grab the NDS stuff, as two of the downloads were as a result of extracting the content of some games aimed at kids. As with anything that anyone extracts from an NDS game, Ninty don’t tend to look on you with bright shiny smiles. So grab ’em whilst you can 🙂

Tools used sections

More guides will be forthcoming on the tools I use / did use to extract the information from both the ZX Spectrum and Nintendo DS will be coming soon.

This also includes my long-winded method on extracting music from NDS games and converting them via MIDI to work in OpenMPT. Although these days it doesn’t support the older Impulse Tracker format, so the guide needs tweaking a little bit first.

Temple of Apshai

Due to the above work on the website, I’ve had to postpone my Atari ST guide on hacking the saved game for this old Epyx title.

The text is approximately 75% complete, but I’ve not made a start on the accompanying saved game editor, which as always, will be coded in GFA BASIC. I might also take a look at the saved game files on other systems too, but that would be a follow-up to the article. AKA don’t hold your breath.

Saved Game Editor source (GFA) available

I’ve been procrastinating for too long. This is an example of the ‘simple shell’ that I created for the majority of my saved game editors.

Get it from this page.

The .ZIP file contains: the hack routine itself, plus a few embellishments like a new GEM font and some music (upgraded to use SNDH format) which plays in the background whilst you’re altering the saved game file(s).

The editor covers the game Legend Of The Sword by Rainbird which was released way back in 1988 (31 years ago!!) and it will allow you to alter the location where your character is currently situated in the game.

The code should be fairly simple to work out and re-use for other games – in case you have an idea for a saved game hack lying around? If you do use it, let me know how easy it was to adapt.

 

All Chip SID Shows now online

After a flurry of work – albeit slowly due to the snail-pace connection at the B & B where I lodge during the week – I’ve created an official page where you can get all episodes (so far) of Max Hall’s SID radio show. This includes the original streams in FLAC format too!

I have recently bought into the MiFi device by Three, which gives me a lot more speed when I’m at the B & B. Here’s hoping it helps speed up the process outlined above.

The FLAC files are, as you would suspect, rather large, so they are hosted on my DropBox account, as are the MP3 versions. However, the MP3 variants are also hosted on this website too, with the exception of episode 10 because it was larger than 128Mb.

I didn’t realise was a limit of download files for WordPress sites hosted by my provider, until it blocked me from uploading this particular episode.

In theory, there will still be a minor delay between the episode being made available on MixCloud through to the FLAC/MP3 files appearing on this page. After all, it’s all done in my spare time, so patience is a virtue.

Click here for the Chip SID Show official download page

 

Latest ChipSID Show (Ep. 9)

Max Hall is back with the latest episode of his ChipSID Show that he does for Radio Free Matlock.

And, as per usual, a few days afterwards, here’s the downloadable MP3 version done by me for Max.

There are the links for the DropBox and Box-hosted variants below. As previously mentioned in other posts, could some of you please try to use the Box one and not just hammer the DropBox one. A few of you are (according to the Bit.Ly stats produced), so my thanks to you.

I am working on finding a “proper” hosting of these files: either via my own website space and/or make an area available on my NAS to share them from there. However, working away from home each week takes its toll on small projects like these, especially when the broadband speed in the B & B I stay in is 1/50th of what I get back home 🙁

Download from DropBox: http://bit.ly/2HTW8is

Download from Box: http://bit.ly/2FScfLp

Enjoy!

Latest ChipSID Show (Ep. 8)

After uploading the previous 7 episodes to my DropBox and Box cloud accounts for Max, he recently sent me the .FLAC file for episode 8.

So after falling asleep (*) whilst waiting for the dual uploads, here are the Bit.Ly links that point to the latest episode.

DropBox: http://bit.ly/2EKSSTF
Box: http://bit.ly/2TsQmK5

(Please try to alternate between the two so that neither cloud host twigs that I’m hosting a radio show!) 🙂

As per the original post, we are using Bit.ly’s URL shortening so that Max can get a rough idea of the total number of downloads.

(*) Mental note: When working away from home (based in the countryside) and using the B&B’s quite slow internet, don’t try and upload the MP3 to both Box and DropBox at the same time … zzzzz

Lending a hand

A good retro mate of mine, Max Hall, has been doing some C64 SID music radio shows on Radio Free Matlock.

His show is called the ‘Chip SID Show’ and a new show is done once a month. You can join his FB support page by clicking the logo above.

Max was hosting the shows in .FLAC format, but as he was using a freebie cloud account, there were a few problems due to their size – weighing in around 2gb for the 7 shows so far – it limited what else he could do with his personal cloud account.

So, to help him out, I’ve converted the .FLACs into .MP3 format and uploaded to my Professional DropBox and freebie Box cloud accounts.

I’ve put the links below in case anyone wants to grab hold of the current collection of episodes.

(Please try to use the alternate links for the various shows. It will help prevent both of my cloud accounts being hammered too much!)

MP3 Downloads for Max Hall’s Chip SID Show

Episode 1:

DropBox: http://bit.ly/2UQD9Yz
Box: http://bit.ly/2TIes09

Episode 2:

DropBox: http://bit.ly/2SHblID
Box: http://bit.ly/2USLOJT

Episode 3:

DropBox: http://bit.ly/2RZkoR2
Box: http://bit.ly/2MY6ihR

Episode 4:

DropBox: http://bit.ly/2Gzv070
Box: http://bit.ly/2X59rB8

Episode 5:

DropBox: http://bit.ly/2TJ9HUj
Box: http://bit.ly/2USMuPr

Episode 6 – Benn Daglish Celebration:

DropBox: http://bit.ly/2Bv2mAK
Box: http://bit.ly/2E4KrlK

Episode 7:

DropBox: http://bit.ly/2BxmySg
Box: http://bit.ly/2USMvTv

Download and listen (and enjoy)!

(The use of Bit.Ly links is purely so that Max can get some sort of download stats …)

Old Windows trainers found

I was trawling through an old hard-drive last weekend and I found a very old website backup from the early 2000s. Within the folder “trainers” were a lot of my old Windows 95/98 trainers which were mostly done using Trainer Maker Kit.

Grab your VirtualBox / Virtual PC, blow the dust off your Windows 95/98 images and track down (if they can be found) some of these old games and play around with these trainers.

The download link is on my Windows 95/98 page.

There’s still a few (e.g. Tomb Raider 4) where all I have left are the .NFO files inside the .ZIP, but not the .EXE trainer itself 🙁

They could be out there in the wide world, but then again, there were (and still are) better trainer makers out there whose work would have been preserved more than mine.

Hey ho, I’m glad I found some of them 🙂

First Blog Post

Welcome!

Well, it’s the first on this site. I used to “do” a blog on an older version of this website way back in the mists of time, but after a run in with a member of staff at the company I was working at, I decided to delete it completely.

The lessons were learned and, with the exception of the blog posts on my “work” website, I haven’t bothered writing one for this site in over a decade!

So, whilst this blog won’t be as “busy” as my Word Toolbox one, I will attempt to use it primarily for site updates and planned site upgrades.

As is the remit to this site, the more “old stuff” that I can find to dump preserve on this site, the better 🙂

Plans for this site in 2019

I’ve got a few plans with regards to more content for this site. Some of it are old plans that just never got sorted out when I first had the brainwave(s), others are completely new.

  • I recently found where I’d stashed an old copy of my “Cheats Always Prosper” website which had (I think) a full set of my Windows 95/98 trainers. So the current page that hosts just one trainer example (that I could find in the wild) will now be updated with *all* of them 🙂

  • Revisiting my old GFA BASIC saved game editors and rework them to use the latest GFA BASIC compiler that Lonny Pursell has been working on.

  • Creating *new* saved game editors for the Atari ST games that “slipped the net” in my youth. I might also get around to finally finishing off and releasing the old DOS-based ones that I’ve been promising to do for years as well!

  • Actually adding the NDS “odds and sods” that I’ve found in my travels. I’ve covered what I’ve found already, but some won’t be allowed to be uploaded (as they are the full source code to the games), but the word dictionaries for old games are probably OK .. I hope.

So the above are the ones I can think of for now. More to come (I hope) in 2019.