I've been hanging around here for years but rarely post - and what I do post rarely makes a difference.
Over the weekend I was poking around and came across the Medieval Mayhem thread. I bought a cartridge version of this from the shop quite a while ago and was impressed - I even took the time to review it in the atariage shop. I live in PAL land so naturally I asked for the PAL version. Very nice it is too - I even read it is speed adjusted for PAL However I noted in my review that the borders are big - paricularly the bottom border. Spiceware created a post containing a version of the ROM for PAL60 - basically (if I understand Spiceware's post right) the timings are for NTSC but with PAL colours.
Being a Harmony cart owner I tried this out - and lo and behold I have full screen Medieval Mayhem - I am delighted.I posted in the MM thread and PM'd Spiceware thanking him.
This got me thinking. If I'm right - then to get a PAL60 version of any game all that is needed is the correct PAL colour values hacked into an NTSC assembly.
I posted some time ago here asking if Kaboom! was optimised for PAL. A kind poster took the time to study the assembly and stated that there wasn't any speed optimisation to be seen in the code. As someone who back in the day could score >300K (albeit at diff B) I was somewhat perturbed that I was playing a less than optimal version of the game.
So today I searched for a Kaboom! disassembly (I downloaded the DASM kit ages ago and did some messing about and then of course abandoned any planned work in that area). I opened up the ASM file and I have to say the 2600 community is a marvel - there it was it in all its commented glory with DASM meta instructions for assembly - showing me the NTSC and PAL settings for colour (not color!!) and frame timings.
So I changed the file to use the PAL colour values in the NTSC part of the file, assembled it, copied it to my Harmony and Holy Mother I now have 60Hz Kaboom! on my PAL woody!!!! I can still bust 10K but I doubt I'll ever get back to the heady days of 6 figure scores - faster game and slower me!!! By the way , I run my woody through a Sony VCR which is connected via SCART to my Panasonic CRT so I'm guessing this is giving me a composite feed into the TV which keeps it happy re the frame rate.
Has anyone created a batch of PAL60 ROMS? I'm keen to create a set if it hasn't been done but I'll be limited to the number of high quality disassemblies that are available (at least initially - I can read 6502 and may get into more involved work if necessary). With a good disassembly this is ridiculously easy to do.
I don't know what the legality of this is (Kaboom! is available in a piss poor version on the PS2) so I won't post the ROM here - however happy enough if I'm allowed to and if anyone wants it. It will be of limited interest as its only relevant to those with a PAL console and a Harmony. There is an impressive amount of tech ability in this forum so this is child's play to most here but there might be those who aren't tech at all and just want the games.
Edited by davyK, Sun Jan 29, 2012 2:01 PM.