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PostPosted: Sun Mar 12, 2017 12:03 pm 
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By chance discovered some printf style string formatting in Color A Dinosaur. There's a lot of text in there that is relevant to DOS/PC implementations too, which is kind of interesting because I don't think it got a DOS release? Anyhow, just another one to add to the list of "might have been written in C".
Attachment:
File comment: printf style formatting of strings in Color A Dinosaur
color_a_dinosaur_c.png
color_a_dinosaur_c.png [ 23.57 KiB | Viewed 2068 times ]


Edit: Altaz on #nesdev clued me in that this has a TCRF entry: https://tcrf.net/Color_a_Dinosaur

Apparently it's a piece of Norton Utilities 7? O_o


Last edited by rainwarrior on Sun Mar 12, 2017 1:15 pm, edited 1 time in total.

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PostPosted: Sun Mar 12, 2017 12:44 pm 
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I'm immediately reminded of "You can't hack me; I got Norton." I wonder if any ROM hackers are up to the challenge of putting a picture related to the "I got Norton" meme (ED; KYM) into the game.


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PostPosted: Sun Mar 12, 2017 12:49 pm 
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Random garbage leftover in RAM when they assembled it maybe?


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PostPosted: Sun Mar 12, 2017 12:50 pm 
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There are some other games which have pieces of random leftover data from the disk (or memory?) in their ROM. I can't name any of the top off my head, but IIRC TCRF should have a few of them (I think one of them had pieces of the game source code). I guess some old tools tried to be clever with optimizations by not clearing unused memory, or only writing disk sectors partially.

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PostPosted: Sun Mar 12, 2017 3:47 pm 
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From 1989 onwards the PC Engine had a CDROM attachment, and since 650 mb was an absurd amount of space back then, the PCE CD devkit was a expensive combo of a PC9801VX with a 620 mb HDD and a 8mm master tape unit plus the Hu7 system which was a regular PC Engine with a huge hardware CD emulation board connected into it. http://i.imgur.com/pqofNGI.png (edit: video of the Hu7 unit: https://www.youtube.com/watch?v=ge9aFCnx5tw)

So what? Well apparently some developers also used the 620mb disk to act as a server for their source code or something like that, because there's an almost complete copy of the original SNK Neo-Geo source code for Art of Fighting stuffed inside the PCE port's retail CDs. Talk about "random leftover data".

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PostPosted: Sun Mar 12, 2017 4:35 pm 
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Punch wrote:
the PCE CD devkit was a expensive combo of a PC9801VX with a 620 mb HDD and a 8mm master tape unit plus the Hu7 system which was a regular PC Engine with a huge hardware CD emulation board connected into it.

Sorry to go further off-topic, but you can see how expensive it was back in the '80s here: http://www.chrismcovell.com/secret/PCE_ ... tml#pcedev ... $144,000!

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PostPosted: Sun Mar 12, 2017 6:49 pm 
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thefox wrote:
I guess some old tools tried to be clever with optimizations by not clearing unused memory, or only writing disk sectors partially.

Actually, if I think about an assembler that needs to output to very slow drive (e.g. tape storage), maybe not clearing unused memory could be a huge time saving on iterations, especially early on in a project when a ROM isn't very full.

An optimization like that which makes little sense now might have been essential on the hardware it was originally written for, and could easily have persisted into the next era where it was no longer necessary.


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PostPosted: Sun Mar 12, 2017 7:47 pm 
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And perhaps then, Symantec wasn't quite as litigious as some companies are nowadays.


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PostPosted: Sun Mar 12, 2017 8:49 pm 
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tepples wrote:
And perhaps then, Symantec wasn't quite as litigious as some companies are nowadays.

I think it's probably more to do with them not being omniscient?


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PostPosted: Mon Mar 13, 2017 9:18 am 
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When you create a file and write a single byte to say 1MB point, the stuff between first byte and the last one is filled with whatever was on the sectors on the HDD that the new file got assigned. Windows NT explicitly zero's out new memory and files, but DOS and Win9x do not.

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PostPosted: Thu Mar 16, 2017 8:47 pm 
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I'm also trying to think why this junk gets into rom images.

Perhaps the tool that ultimately creates the rom image declares one large chunk of RAM, but never bothers to zero or $FF it.
The system RAM on the host computer of course contains data from other programs that were loaded into its RAM previously.
The tool creating the rom image goes from bank to bank, and just stops copying early if the source data for that bank does not completely fill it.
Ending earlier at the bank of course leaves the previous data there.

When done, the entire chunk of RAM is copied to the rom image file, that is later sent to the EPROM writer or onto a floppy disk.

Otherwise I can't fathom that one would copy raw sectors from a storage disk-- it seems like more effort to read raw sectors than read and write from the filestream.


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PostPosted: Fri Mar 17, 2017 4:03 am 
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'm gonna expect t was more a tape reuse deal.


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PostPosted: Fri Mar 17, 2017 10:27 am 
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I definitely remember writing programs in C, compiled with Borland Turbo C++ v3.0, running in x86 real mode under DOS, and allocating memory using malloc (which makes no guarantees about the contents of the memory when allocated, unlike calloc) and finding random crap in the allocated memory blocks.

To me, it feels like a safe assumption that this is the entire cause.


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PostPosted: Sat Dec 02, 2017 6:53 pm 
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I thought this was a joke entry (like "Uncyclopedia" does) when I saw it recently, but that seemed out of character for TCRF. Then I opened my hex editor and had a good laugh. Wow, it's real.

I wonder if, for similar reasons to those stated above, this could be an artifact of the dumping process (random chunks of the dumper's harddrive sectors or RAM contents). Who knows what silly copying techniques people used when they first dumped this probably 20 years ago?

Well, I'm not gonna be the one to go to Ebay and play repro-roulette at $100 a cart to get a verified dump. I did ping @JayObernolte on Twitter trying to get some info.


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PostPosted: Sun Dec 03, 2017 1:42 am 
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I believe you are mistaken, BillyWM.

It's not a "bad dump", like somone making a recent copy screwed up.

In my opinion, it's a build (by the original producers) that didn't zero the contents of its memories it was using (reusing), and just left whatever contents were there. And copied it in entirety onto the original ROM.

There's no reason to believe it won't play correctly.

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