Donkey Kong Trainer

[Sock Master]

A bug in DK Trainer has been discovered by Jason Wade.
If the board skip function is being used while the game is paused, it can muddle up some of the in-game statistics bookkeeping - some desyncing between your score and your pace may occur.

Specifically, it happens if you try to skip a board before it is finished processing an in-progress board skip...  I guess sort of a time distortion in processing.   This can also happen if you set the game speed very slow and try to skip boards twice in quick succession.

The not so bad news is that this can easily be avoided if you know what triggers the glitch.
If you've paused the game or are playing at low speed, avoid skipping boards in rapid succession.

I'll update the ROM with a fix soon.  The fix will simply disable the board skip button at times that it's already in the middle of processing a board skip.

[pser1]

Hi,
I am a newcomer to MAME, I have downloaded v0.178b that works flawlessly
with the standard dkong.zip
As soon as I substitute the four modified roms copying there the new ones
it is no more recognized by MAME that says:
The selected machine is missing one or more required ROM or CHD images.
Please select a different machine
This reminds me something about the CRC of each ROM.
As I change the ROMs, how could I avoid that CRC checking?
Any advice will be greatly appreciated
Thanks beforehand
pere 

[pser1]

Hello,
I am copying here the result of this command for maybe it could help find the solution ...
mame64 -verifyroms dk* >errordk.txt

dkong       : c_5et_g.bin (4096 bytes) - INCORRECT CHECKSUM:
EXPECTED: CRC(ba70b88b) SHA1(d76ebecfea1af098d843ee7e578e480cd658ac1a)
   FOUND: CRC(7ed5a945)
dkong       : c_5ct_g.bin (4096 bytes) - INCORRECT CHECKSUM:
EXPECTED: CRC(5ec461ec) SHA1(acb11a8fbdbb3ab46068385fe465f681e3c824bd)
   FOUND: CRC(98e2caa8)
dkong       : c_5bt_g.bin (4096 bytes) - INCORRECT CHECKSUM:
EXPECTED: CRC(1c97d324) SHA1(c7966261f3a1d3296927e0b6ee1c58039fc53c1f)
   FOUND: CRC(098a840a)
dkong       : c_5at_g.bin (4096 bytes) - INCORRECT CHECKSUM:
EXPECTED: CRC(b9005ac0) SHA1(3fe3599f6fa7c496f782053ddf7bacb453d197c4)
   FOUND: CRC(dd092591)
romset dkong is bad

regards
pere

[Sock Master]

This reminds me something about the CRC of each ROM.
As I change the ROMs, how could I avoid that CRC checking?
Any advice will be greatly appreciated
Thanks beforehand
pere

Any new or modified version of a ROM set will not have built-in support in MAME.
The DK trainer ROMs are a plug-in replacement for the regular Donkey Kong ROMs, but as they contain different contents so MAME will report that the CRC does not match the original ROMs.

New versions of MAME when using the GUI (graphical user interface) will prevent you from running a modified ROM.  I'm not sure if there's some setting you can change to allow it.. maybe someone can chime in.
But you can run MAME from the Command prompt and that lets you play the DK Trainer ROM.   Yes, it'll still report that the CRC is incorrect, but you just type OK and it'll run.

Old versions of MAME might allow you to play DK trainer using the GUI, but I'm not sure which.

[pser1]

Hello,
thanks a lot!
It works nicely from the command line, I didn't know.
I thought it was mandatory to change the CRC of each file!
I did that to emulate CoCo and Dragon machines to test
different DOS versions and it was painful 

You are doing a great job, cheers!
pere

[bdegg]

 I love this trainer, it's super helpful, but I really find the spring length numbers distracting on the elevator screen. Is there some way to hack those scrolling numbers out of the trainer?

I practiced springs using save states before I found the trainer, and I'm pretty OK at them but when I get to the springs on the trainer I'm terrible because the numbers make that area of the screen a lot busier. 

I'm comfortable with using a hex editor and I briefly messed with the MAME debugger trying to figure out a way to remove them, but I figured asking in here would be my best bet.

[Sock Master]

I love this trainer, it's super helpful, but I really find the spring length numbers distracting on the elevator screen. Is there some way to hack those scrolling numbers out of the trainer?

The older version of DK Trainer had the scrolling numbers on the right side of the screen, but the current version has them on the left, above DK himself.   They're in a less distracting location.

I'm not sure which version of the trainer you're using.  A hack to modify the ROMs would vary depending on version of DK Trainer.   If you have an older version you can go to the first message of this tread and get the .zip file that's linked in it.

[bdegg]

I have the current version, with the scrolling numbers on the left above Donkey Kong. Ideally I'd just want to hack them to be gone.

I find that when I'm trying to concentrate on watching the spring placement I can't help being distracted by the numbers and that throws me off, lol. I do much better with the springs on a stock DK rom, I hardly ever die on the elevator screen and when I do it's usually an embarrassing failed jump or fireball mishap.

[Sock Master]

I have the current version, with the scrolling numbers on the left above Donkey Kong. Ideally I'd just want to hack them to be gone.

Ok, after some quick checking.. if you modify ROM addresses $3137 and $313C to both contain byte $3A  (originally they both contain $32), it should disable the spring numbers from appearing on the screen.

If you're modifying the .bin files, that would correspond to the $0137th and $013C bytes of the c_5et_g.bin file.   Both originally contain values of $32, replace with $3A.

[bdegg]

Did you mean c_5at_g.bin? The c_5et_g.bin didn't have $32 values in those locations but c_5at_g.bin did.

I changed them to $3A and the numbers are definitely affected but they're still there..  looks like only one digit appears now? And the number doesn't seem to be related to the length of the spring. At first they don't scroll but after a couple springs the scrolling resumes.

[Sock Master]

Oops, I think I must have miscalculated the location of one of the two addresses listed in my previous message by one.

There should be this sequence of bytes $0C $D6 $0A $32 $86 $77 $79 $32 $A6 $77 $3E $0A in the binary.
Changing both of the $32 values into $3A will prevent the Z80 code from writing the numbers onto the screen.

[bdegg]

Works perfectly, thank you!  The numbers don't appear any more!

The correct addresses to change from $32 to $3A turned out to be $3133 and $3137.

[QAOP Spaceman]

A bit late to this, but 

Such great work, Sock Master...

Thank you!

[captnkong]

Can anyone tell me if it’s possible to run this program on a raspberry pie?  I’m thinking that I can find an old. Erosion of MAME or mame4all that will allow a command line game to run it should work with retropie so I was wondering if anyone has done this.

[captnkong]

Just FYI for anyone who is wanting to do this on a raspberry and or bartop; once I got the program loaded up on a new retropie install I put the rom in the MAME libretto folder. You then need to go into the retropie/bios folder and creat a new folder called mame2003. Once inside that folder u need to creat a file called samples.  In that file put your zipped donkey Kong sound files needed to play to play on older versions of MAME.  This 2003 emulator is the only one I can find that will play the donkey Kong training program within retropie; it does play great from a normal command prompt within any MAME version but I wanted this on a bartop running retropie and now it works.  I’m sure if your handy around a retropie you could get to a command prompt and run it as well but I’m not that savvy.