unorig
@unorig.bsky.social
Reverse engineering Commodore 64 games.
I now have a tile editor for the mine level of A View to a Kill for the Commodore 64. The level was always interesting to me but was terribly cramped and difficult to get around. Now I can give the level a lot of space.
October 23, 2025 at 8:53 AM
I now have a tile editor for the mine level of A View to a Kill for the Commodore 64. The level was always interesting to me but was terribly cramped and difficult to get around. Now I can give the level a lot of space.
I now have a map viewer built in for Paris and Mine levels of a View to a Kill for the Commodore 64. One is character based and the other is tile based which makes things more complicated. However, soon I will be able to modify the maps to make them a little less frustrating to play.
October 20, 2025 at 9:56 PM
I now have a map viewer built in for Paris and Mine levels of a View to a Kill for the Commodore 64. One is character based and the other is tile based which makes things more complicated. However, soon I will be able to modify the maps to make them a little less frustrating to play.
I always found the arrows on the roads of the Paris level of A View to a Kill for the Commodore 64 really confusing. So now I have a character and map editor where I can change the arrows to dashes straight into an uncompressed PRG.
October 19, 2025 at 12:01 AM
I always found the arrows on the roads of the Paris level of A View to a Kill for the Commodore 64 really confusing. So now I have a character and map editor where I can change the arrows to dashes straight into an uncompressed PRG.
Since there isn't Charpad for MacOS so I have been trying to build a character / map editor for MacOS. It's not pretty, but I can now see the Paris map for A View to a Kill.
October 17, 2025 at 10:17 PM
Since there isn't Charpad for MacOS so I have been trying to build a character / map editor for MacOS. It's not pretty, but I can now see the Paris map for A View to a Kill.
One of the things that really frustrated me about A View to a Kill - Paris level for the Commodore 64 was the wall collision. Coding a solution would basically be a ground up rebuild so I have decided to shorten the car to greatly reduce this issue - way better. Now to make it multicolour.
October 17, 2025 at 2:26 AM
One of the things that really frustrated me about A View to a Kill - Paris level for the Commodore 64 was the wall collision. Coding a solution would basically be a ground up rebuild so I have decided to shorten the car to greatly reduce this issue - way better. Now to make it multicolour.
Ive also now got the ability to view and edit the sprite. Not sure how useful it would be to make modifications to a sprite while reverse engineering yet, but it's there for my amusement.
October 14, 2025 at 11:59 PM
Ive also now got the ability to view and edit the sprite. Not sure how useful it would be to make modifications to a sprite while reverse engineering yet, but it's there for my amusement.
Added the ability to define .word, .text, and also sprites. This makes the program use less rows and a bit more manageable to read.
October 14, 2025 at 8:46 PM
Added the ability to define .word, .text, and also sprites. This makes the program use less rows and a bit more manageable to read.
GitHub user pditincho has taken apart the C64 version of Maniac Mansion - perfect for anyone curious enough to PEEK into the game’s code. github.com/pditincho/mm...
GitHub - pditincho/mm-explained: Maniac Mansion C64 explained
Maniac Mansion C64 explained. Contribute to pditincho/mm-explained development by creating an account on GitHub.
github.com
October 8, 2025 at 6:13 AM
GitHub user pditincho has taken apart the C64 version of Maniac Mansion - perfect for anyone curious enough to PEEK into the game’s code. github.com/pditincho/mm...
Sometimes you need 'Cautious', then sometimes you need...
October 7, 2025 at 10:57 PM
Sometimes you need 'Cautious', then sometimes you need...
This is the weirdness of disassembling C64 Assembly. Someone leaves a random address or code somewhere that the program never gets to, but messes up disassembly.
October 7, 2025 at 9:11 PM
This is the weirdness of disassembling C64 Assembly. Someone leaves a random address or code somewhere that the program never gets to, but messes up disassembly.
Due to the randomness of C64 Assembly, I have had to make an option of 'Aggressive' or 'Cautious' disassembly. I found that sometimes you need to step through sections and find the buggy code before disassembling. Paris Chase in A View to a Kill was fine on Aggressive, but City Hall has some bugs.
October 6, 2025 at 9:57 PM
Due to the randomness of C64 Assembly, I have had to make an option of 'Aggressive' or 'Cautious' disassembly. I found that sometimes you need to step through sections and find the buggy code before disassembling. Paris Chase in A View to a Kill was fine on Aggressive, but City Hall has some bugs.
There are some scaling issues but it looks like I have a build of my disassembler working on Windows now too.
October 5, 2025 at 10:28 PM
There are some scaling issues but it looks like I have a build of my disassembler working on Windows now too.
Much better on MacOS now.
October 4, 2025 at 4:57 AM
Much better on MacOS now.
Testing my disassembler in MacOS. It builds - but it's pretty ugly. I still prefer using Linux as an OS than MacOS.
October 4, 2025 at 12:58 AM
Testing my disassembler in MacOS. It builds - but it's pretty ugly. I still prefer using Linux as an OS than MacOS.
I can now manage self-modifying code. Getting close to having all the program just use labels rather that direct memory addresses.
October 3, 2025 at 4:48 AM
I can now manage self-modifying code. Getting close to having all the program just use labels rather that direct memory addresses.
Added symbol management to my disassembler. I can now select a symbol, press F3 and go to the next usage of the symbol too.
September 30, 2025 at 10:33 PM
Added symbol management to my disassembler. I can now select a symbol, press F3 and go to the next usage of the symbol too.
Making some good progress on my disassembler. Its the most promising version of a disassembler I have ever made. I am 70% through mapping out A View to a Kill Paris level which is good. I think the last 15% will be bizarre junk.
September 29, 2025 at 6:41 AM
Making some good progress on my disassembler. Its the most promising version of a disassembler I have ever made. I am 70% through mapping out A View to a Kill Paris level which is good. I think the last 15% will be bizarre junk.
My C64 disassembler is getting to a point where I am spending more time disassembling than updating the disassembler. It now has handy features like percentage categorised and the ability to copy sections to ASM so I can get AI to help understand sections.
September 26, 2025 at 11:54 PM
My C64 disassembler is getting to a point where I am spending more time disassembling than updating the disassembler. It now has handy features like percentage categorised and the ability to copy sections to ASM so I can get AI to help understand sections.
Well I now have my C++ disassembler disassembling to 64tass format, compiling to a prg and making a self-extracing prg with exomizer in Linux. It is now also launching in RetroDebugger. This is good because I can continue to disassemble to see when the disassembler doesnt do a good job.
September 23, 2025 at 10:27 AM
Well I now have my C++ disassembler disassembling to 64tass format, compiling to a prg and making a self-extracing prg with exomizer in Linux. It is now also launching in RetroDebugger. This is good because I can continue to disassemble to see when the disassembler doesnt do a good job.
Build a new Commodore 64 Disassembler in C++ this time. Allows me to group sections for readability.
September 22, 2025 at 10:01 PM
Build a new Commodore 64 Disassembler in C++ this time. Allows me to group sections for readability.
My Gnome C64 disassembler now has data blocks and can put start and end comments around a data block.
February 10, 2025 at 2:09 AM
My Gnome C64 disassembler now has data blocks and can put start and end comments around a data block.
Some good progress on the Gnome C64 Disassembler. It now has all the buttons working and I can save and load a project.
January 21, 2025 at 10:48 AM
Some good progress on the Gnome C64 Disassembler. It now has all the buttons working and I can save and load a project.
Making some good progress on my Gnome C64 Disassembler. It how has some nice features like "Make data block", "Jump to memory address" (If the row contains a JSR, JMP, BEQ, etc), and also bookmarks. Bookmarks are handy to make areas of focus.
January 18, 2025 at 2:53 AM
Making some good progress on my Gnome C64 Disassembler. It how has some nice features like "Make data block", "Jump to memory address" (If the row contains a JSR, JMP, BEQ, etc), and also bookmarks. Bookmarks are handy to make areas of focus.
I can now add and update labels on code and adjust the starting memory address in my Gnome C64 Disassembler. The code is very messy and needs to be refactored, but making some good progress.
January 14, 2025 at 9:46 AM
I can now add and update labels on code and adjust the starting memory address in my Gnome C64 Disassembler. The code is very messy and needs to be refactored, but making some good progress.
My code is pretty hacky at the moment but I now have branching logic working along with JMP operations in my Gnome C64 debugger. The hardest part has been learning Vala - and some object oriented programming concepts. Its certainly different from Assembly which I am used to.
January 11, 2025 at 11:31 AM
My code is pretty hacky at the moment but I now have branching logic working along with JMP operations in my Gnome C64 debugger. The hardest part has been learning Vala - and some object oriented programming concepts. Its certainly different from Assembly which I am used to.