Question about Dragonfire difficulty switches

[Serious]

Hi everyone,

 

I'm doing some cleanup of the difficulty settings in the highscore.com database, aided by some fellow AtariAge members.

 

When reviewing the Dragonfire manual, it makes no mention of the use of difficulty switches, so we assumed (at first) that his meant that the difficulty switches have no effect on this game.

 

However, if you look at the scores on the game with difficulty set to A and B, there is an obvious difference:

 

Dragonfire (Atari 2600 Expert/A)

 

4,300 killersquirel <<

2,930 Serious

2,810 S.BAZ <<

 

 

Dragonfire (Atari 2600 Novice/B)

 

8,780 killersquirel <<

7,280 heywoodfloyd

4,300 S.BAZ <<

 

 

So, two of the same players scored almost twice as much in difficulty mode B than mode A.

 

 

I took a look through the source code, and found this:

 

;

; DELTA FIREBALLS

;

LDA FPCTL ; DO FIREBALL SPEED WITH WAVENO E DIFF

ASL ; SHIFT DIFFICULTY TO CARRY

LDX PLAYNO

BNE SKIP34

ASL

SKIP34

LDY WAVENO

LDA #0

ADC FBSPEEDS,Y

STA T0

LDX #NUP0S-1

DEFBLOOP LDA P0YS,X

CMP #DEAD

BEQ NEXT05

ADC T0 ; FIREBALL SPEED

IF PAL

CMP #$95+15

ELSE

CMP #$95

ENDIF

BCC OKXX

LDA #DEAD

OKXX

SKIP18 STA P0YS,X

NEXT05 DEX

BPL DEFBLOOP

 

Without understanding the routine here, based on the comments, it appears to me that the fireball speed may be different based on the difficulty settings.

 

I would appreciate any insight from someone who can decipher the source, or who knows the game better than I do.

[+Omegamatrix]

You are correct, the difficulty switch is used by this game. Also you have correctly found the place where it is used in the rom. When the difficulty switch is in PRO position the fireballs are faster.

 

 

Kudos on being able to understand enough of the assembly to find that.

[Serious]

Thanks very much for the help!

[NIKON]

Here is a video comparison...

 

http://www.youtube.com/watch?v=LJcJ09Oa9QM&feature=youtu.be

[SoulBlazer]

Why wasn't this mentioned in the manual? I thought the differences in difficulty switches as a big thing back then.

[+Omegamatrix]

Why wasn't this mentioned in the manual? I thought the differences in difficulty switches as a big thing back then.

Yeah, who knows? Maybe they thought it would be obvious to the user and it was an oversight.

 

What's worse are games that use the other controller port and don't make mention of it anywhere. Towering Inferno comes to mind!