Gameboy Camera - Force Trippy H (Page 1 of 3)

Could you just modify the JP instruction at 0100-0103 to go straight to Trippy H instead of the normal menu location?

I'm out of my league here.

Ok. By replacing $40DB with "LD A, $1F" the player may never leave Trippy H. This allow for us to remove unused routines and officially make this a Trippy-H-dedicated ROM.

IDK about that. I feel like there is more to it than a simple jump.

If a simple jump is what you want, then I think you need to locate a write to $D5CE with $1F. This is the byte which says which mode we are playing. 1F pertains to T-H.

Performing a write break of 1F to that location (when I shoot the Dj-spaceship) is at $568B:

LD A, $1F
LD [$D5CE], A
...

This should return to the main loop after a few more commands. You could try that.

How about the Routines that check if the camera is present?

Thanks Ben. Did you change the cart type in header too? I haven't tested it out on a real cart yet, but my version that skips the other menus never touches A000.

Oh, did you find that fix after we skyped and took apart GB cameras together? xD

Last edited by Jazzmarazz (Jan 25, 2016 6:25 pm)

I am currently stepping through thousands of loops to find that ONE routine that wipes SRAM before the "gamefreaks" logo. SRAM is seemingly randomized and then cleared but it never breaks for me...so I am searching by hand. You say it is checked before any graphic operations wich 'looks' correct when watching the SRAM in real time, but it never breaks!

I have already wiped the routine that triggers the A000 check when you press "shoot" but I just can't find the pre-graphics check.

My method for picture dumping was to copy the save to my Mega Memory Card and then to an EMS and then to PC. No trading or hacking needed.

EDIT1:

The routine at $0462 is as follows:

XOR A
LDI [HL], A
DEC BC
LD A, C
OR B
JR NZ, $0462

This routine is always jumped to after these two lines:

LD HL, $xxxx
LD BC, $xxxx

Where the word stored in HL represents a memory address and the word stored in BC represents the number of times to repeat the routine at $0462. The routine itself clears every byte to 00 in this range. For example, the below code will place 00 in every byte from A000 to AFFF.

LD HL, $A000
LD BC, $1000
CALL $0462

Last edited by Jazzmarazz (Jan 26, 2016 12:08 am)

A major improvement I would like to make, but am not skilled enough to do, is add a second Pulse channel to Trippy H.
There are three tabs listed as: Sound I, Sound II and Noise, where these represent Pulse 2, Wave, and Noise respectively. Pulse 1 is used for menu sound effects like quitting and saving.  This is useless.

Here is Tab 1, but controls the registers of Pulse 2. You can switch between 3 different pulse width options, even though the gameboy is capable of 4.

Here is Tab 2 called Sound 2, but it controls the wave channel. As you can see, there is a custom waveform being played. There are three options, 1. Pulse with 50% width, 2. the sample you can see and 3. a hand drawn waveform.

And here is the Noise Tab which controls the noise registers. Decent percussion loops can be made here.

For the above three, I would like to remove the Trippy-H text at the top right to make room for a duplicate of Sound I which will control Pulse 1.
Changing their names will be an easy graphics swap once I locate the sprite storage. All of the tabs will be shifted right.

On this page, I would like to remove the "SE" tab. The other tabs can then be shifted to the right to accommodate the addition Pulse 1.

The coolest thing about Trippy-H is the frequency modulation option. At the top right of Sound 1 and Sound 2 control, there is a Modulation box. You can adjust the amplitude of modulation, frequency of modulation and waveform of the modulation.