How to Modify Games to Load on a CMD HD

We all have a favorite Game on the Commodore 64, and the first thing a lot of people do when they buy a CMD Hard Drive, is try to get that Multi-Load Game working on it.

In many cases, you do not need to be an expert to get Games to Load & Run on a CMD-HD or CMD-RAMLINK. In many cases, You do not need to know Machine code or how to use an Assembler.

This article is written for the Non-Experts out there, as there are a lot of things you can try, as long as you have a few basic items & a the free time to experiment, until you get the Game working.

For those wanting Expert Advice on the topic of fixing Games to work on a CMD Hard Drive or CMD SuperCPU, Click here to be taken to the Expert Article.

 

Here is the Index for this HOW TO webpage:

WHAT TOOLS DO I NEED?

WHY DOES A GAME NOT LOAD & RUN ON A CMD HARD DRIVE?

TEST THE GAME FIRST, AS IT MAY NOT NEED ANY FIXING!

MODYFYING THE "GAME BOOT" ONLY !

MODYFYING THE "GAME BOOT & LOADER" !

FILE NOT FOUND ? WHY ?

TRACK DOWN ANOTHER VERSIONS OF THE GAME !

MODIFYING THE CODE IN THE GAME TO GET IT TO LOAD.

WHAT CAN WE DO TO A CMD HARD DRIVE, to get Games to LOAD & RUN on it.

 

How to Modify Games to Load on a CMD HD:

WHAT TOOLS DO I NEED ?

Action Replay For FREEZING & SAVING and also for TURBO LINKING. You can also try other Cartridges that have a Freeze & Save option.
Super Crunch In case the FROZEN Game is larger that 202+ Blocks (or any other Cruncher that is easy to use)
CMD Hard Drive For testing the Game on, After modifications.
1541 Floppy Drive For testing the Game on, Before modifications.

To know how to Fix a Game, you first need to know "What needs fixing" , or What is stopping the game from Loading, so this is what I will discuss next.

 

WHY DOES A GAME NOT LOAD & RUN ON A CMD HARD DRIVE?

IRQ Loader If the programmer has written his own loader, this will not work with the Hard Drive 95% of the time. Some IRQ Loaders work with hard drives.
Track & Sector Some games do not load Files for data or levels, instead they load whole tracks. 99% of these will not work on a hard drive.An example of this is the game "Alice in wonderland".
1541 ROM / DOS Some games use Software that is located in the 1541 ROM, to load the game from the disk. The HD ROM is similar but not the same as a 1541.
Fast Loader Fast Loaders can be "IRQ", "software speed up" or "1541 ROM" dependent so these will also not work on any Non-1541 Drives.
Original Protection Some Games have Errors on the disk that were placed there by the makers of the game. You cant copy Errors onto a HD, so when the game checks for the Error, it knows the game is a Copy & so it will not work.
Fake Filenames The Directory can be modified to hide the real filenames that appear in the list, and display fake names, or names with hidden letters. This makes file copying impossible, as the drive will report FILE NOT FOUND error, An example of this is the game "Bonanza Brothers".

 

TEST THE GAME FIRST, AS IT MAY NOT NEED ANY FIXING!

(1) With the C64 turned off, connect the CMD Hard Drive, Monitor, Joystick, all power cables, and then Insert your Action Replay Cartridge. Turn the computer on press "F1 - CONFIGURE MEMORY", as this will clear the computers memory and hide/Disable the Action Replay.

(2) For best compatability, First copy the game onto a 1541 Emulation partition using MCOPY & Try loading the game using the Hard Drive as Device 8. (press SWAP 8).(Jiffydos switched ON)

(3) If the above idea fails, try to load the game again, but this time, turn Jiffydos off.

In many cases the Game will work just fine on the CMD Hard Drive, and you will not need to Fix or modify the Game. But you should rename the first file on the disk to say "HD-LOADS" so that in future you know that this game works on the hard Drive without any modifications.

 

MODYFYING THE "GAME BOOT" ONLY !

(1) With the C64 turned off, connect the CMD Hard Drive, Monitor, Joystick, all power cables, and then Insert your Action Replay Cartridge. Turn the computer on press "F1 - CONFIGURE MEMORY", as this will clear the computers memory and hide/Disable the Action Replay.

(2) For best compatability, First copy the game onto a 1541 Emulation partition using MCOPY & Try loading the game using the Hard Drive as Device 8. (Jiffydos switched ON)

(3) If the above idea fails, try to load the game again, but this time, turn Jiffydos off.

(4) If the above idea fails, Select the 1541 Emulation partition on your CMD HD, then Set the CMD HD as device 9 ( press SWAP 9), next load the game from the 1541, the game will Load perfectly from the 1541.

(5) Once the first part of the game has loaded, do not press any keys or joystick buttons, press (SWAP 8) on the Hard Drive to see if you can make the HD device 8.

(6) Now you can press Keys or Joystick button to try to get the rest of the game to load. You may find that that rest of the game loads perfectly from the HD, in this case, all you need to do is Freeze the Game after you have loaded it from a 1541 and save this and call it HD-LOADER. (If the file is larger than 202 Bloacks, you will need to Crunch the program or it will not work on any Computer or Drive unless the Action Replay is Installed & Enables.

If this did not work, Turn the computer & all drives OFF and then try the GAME BOOT & LOADER method below.

MODYFYING THE "GAME BOOT & LOADER" !

(1) With the C64 turned off, connect the CMD Hard Drive, Monitor, Joystick, all power cables, and then Insert your Action Replay Cartridge. Turn the computer on press "F1 - CONFIGURE MEMORY", as this will clear the computers memory and hide/Disable the Action Replay.

(2) For best compatability, First copy the game onto a 1541 Emulation partition using MCOPY & Try loading the game using the Hard Drive as Device 8. (Jiffydos switched ON)

(3) If the above idea fails, try to load the game again, but this time, turn Jiffydos off.

(4) If the above idea fails, Select the 1541 Emulation partition on your CMD HD, then Set the CMD HD as device 9 ( press SWAP 9), next load the game from the 1541, the game will Load perfectly from the 1541.

(5) Once the first part of the game has loaded, do not press any keys or joystick buttons, press (SWAP 8) on the Hard Drive to see if you can make the HD device 8.

(6) Action Replay freeze the game and select "TURBO LINKER", then select "DISK Device 8". Exit the Freeze menu.

(7) Now you can press Keys or Joystick button to try to get the rest of the game to load. You may find that that rest of the game loads perfectly from the HD. If this works 100% then turn off the computer, follow these instruction again and this time, at step (6) above, after you have select the TURBO LINKER, return to the Action Replay menu and select SAVE GAME.

(If the file is larger than 202 Bloacks, you will need to Crunch the program or it will not work on any Computer or Drive unless the Action Replay is Installed & Enables.

FILE NOT FOUND. WHY?

With many games they will seem to work up to a certain point, and then loading suddenly stops with the Red Error light flashing on the CMD HD. If you reset your C64 and type "@" to read the error channel, a lot of the time you will get the error "FILE NOT FOUND". The first thing I would do at this point in time is check memory location $0230 using a Monitor like the Action Replay . In an effort to see what is the FILENAME that the Game is searching for.

You may very well find that the Filename of one of the game parts has illegal characters in it and was not copied to the HD when you file copied the game.

Once you know the right filename that the game is looking for, you can use a Directory editor to Rename the file to something Legal, then copy it to the HD and then rename it back to the correct Filename that the game wants. My copy of Bonanza Brothers required this for one of the Levels.

TRACK DOWN ANOTHER VERSION OF THE GAME !

If you cant get a game to Load on the CMD HD, and you have already wasted a lot of time trying, You may be better off looking for another version of the Game. For example, I tried to get the Game "SINBAD" (Which is a Track & Sector game), to load on my CMD HD with no success. I then looked on the Internet and found another versions of the same game, that someone had already worked on and converted both sides of the Game disk to Multi-load FILES. And this version worked on the Hard Drive without any further modifications to the game.

So instead of wasting your time converting games, it is sometimes better to Hunt on the internet for a game that someone else has already modified and may just work on the Hard Drive as-is without any work on your part. You may also find a game that has already had 90% of the work done on it and all you need to do is 10% of the work, in the form of fixing the GAME BOOT or LOADER.

MODIFYING THE CODE IN THE GAME TO GET IT TO LOAD.

For those of you who are experienced programmers, you may want to modify the machine code to get the game to work on a CMD Hard Drive or CMD SuperCPU, Click here to be taken to the Expert Article.

 

WHAT CAN WE DO TO A CMD HARD DRIVE, to get Games to LOAD & RUN on it.

1541 EMULATION PARTITION

This is the by far the most compatible method in the world today as it is an exact clone of a 1541 disk side. It actually works with Track & Sector which is an incredible achievement by CMD. The only weakness with this like all non-Commodore gear is the ROM in the Hard Drive is not 100% identical to the 1541 Disk Drive

1541 SUBS This is a utility that comes with the CMD Hard Drive and rquires you to first make a NATIVE partition and then run 1541 SUBS to create a Directory on the hard Drive partition's TRACK 18, which is exactly where a 1541 stores its Directory. You then file-copy the entire game onto this partition and it might then work as-is without modifying the game at all.
DISABLE JIFFYDOS This is an easy thing to try by simply flciking the switch and turning off Jiffydos, You might find that the game has a special Loader that will not work with Jiffydos, and the Game may work with it turned off completely. The only down side to this is that the CMD Hard Drive is slower than a 1541 Disk Drive if you use it without Jiffydos, so this method is very slow to test.
MAVERICK PARAMETERS See Section 8-3 of the CMD Hard Driver Owners manual, it explains how to use MAVERICK PARAMETERS to make copies of Games disks work in 1541 Emulation partitions.
DISABLE Burst & Fast Serial

Try DISABLE Burst & Fast Serial by tying the command:

@U0>B0

SWAP 8 Most Game makers expect the 1541 to be at Device 8, so by SWAPPING 8 , right from the start before you try anything else, The game may actually work as-is.

Well, I hope these Tips have given some of you the starting points with which to dive into converting your own games to work on a CMD HD.

The Final advise I will offer is before you try converting a Game, first check the list of games that have already been converted as someone may have already done all the work for you. Click here to check the list of Games that have already been converted or tested on a CMD HD.

Written by The Vortex, on 19-01-2010

Updated :10-10-2010

 

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