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Any PGM Conversion info out there?

Hm, not quite. Still getting the same bunch of strings and repeating output in a 'recrypted' dump for some reason.
And to be clear, i compiled a special mame with the order of actions reversed. Seems that the order in which the actions are performed is indeed 'both ways' so this code change/trick wasn't needed.

Still need to figure out why the crap output.
 
The macros (IGS27_CRYPT1_*) do some munging of the x value as well... maybe worth expanding the macros and looking what it does in which order?
 
Anyway, as it's Christmas i put some time into playing the game (DDP BL).

Is it normal for the
- Breakbeat during ship selection to almost sound like white noise/oversteered?
- Voice sample (singing) appears almost like an 8 bit / 6 bit sample
- General audio quality is a bit hissy or too much high?

I've owned a PCB version of Espgaluda and that was nicely 'muffled' or 'bass-like' bit this is almost too clear and not masking anything :(

I can't compare to MAME as that's not quite the real thing compared to PCB/Cart, so how do others think the sound quality is on cart?
 
I haven't noticed any differences between the boots and the PCBs but I've only played on low volumes through the cab speakers using V1 motherboards.
 
Make no mistake the audio is pretty crap sounding but so were the PCBs, definitely very muddy sounding.
 
Asure said:
- Voice sample (singing) appears almost like an 8 bit / 6 bit sample
Click to expand...
The sample ROM is 8-bit wide, so you could be right on that*. :) You can do some special encoding to increase dynamic range, but I have no idea how much. (And with my old ears I can probably not tell the difference.)
Then there is the question at which sampling rate they stored the samples to preserve ROM space.

* The datasheet says that the chip supports 16-bit samples, but the mame sources said the rom contains 8-bit 11kHz samples. I guess looking at the audio setup that many arcades have it is possible they went for the option that supports most sound data for the ROM space.
 
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well the PGM uses a Z80 for sound processing doesn't it? Honestly the sound is pretty impressive considering.


But as I said in my Sheep Nova vs Lydz review one cart had scratchy audio while thr other did not.
 
Most of the actual sound playback is done by the ICS2115, which was used for some PC sound cards at that time. The Z80 just has to update registers a few times each frame. I find it quite interesting that they use a MOD-based sound format, though.

Is there a chance that the cart with the scratchy sound was written with the wrong endian? As the audio data is stored digitally the only ways it could sound wrong are a bad dump or data written with opposing endian. (Assuming no bit rot on the EPROM or dodgy wiring.)

Of course, data could be stored at a lower quality to fit into a smaller ROM, but then you'd have to patch the playback data for new offsets which may be too much trouble for the money you save...

Link to datasheet: http://www.audioschematics.dk/downloads/schematics/soundcards/wavefront ics2115.pdf Looks like if you want 16 bit samples you'll need to connect two roms?
 
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Re: Sound
I've no idea but i guess we'll have to live with it, as it seems this is confirmed by another user so far.

As for the DDP DOJ White/Black label, i might have a lead on a AMB cart in my country that i can borrow and dump.
Still i rather open pandora's box and figure out the (re)encryption properly. I'm sure in the next days i'll stumble across something i missed.

Also, the DDP DOJ version that we have on the carts (Tagged by AMB in the header) appears to be the later black+white version, it has the setting for old/new bonus lives in the service menu, it just boots to black label always.

Also i see several copies(?) of the game at 0x100000 and 0x200000 and they have a reset vector 0x13b7b8 and 0x23b7b8 for some reason, game jumps between them as well (?). Plus the DOJ and DOJBL strings/0x200 header at the start is there as well.

@Apocalypse did you run unencrypted code from a cart at any point?
 
I was able to successfully get Espgaluda running on my non-Nine Dragons KOV2 cart #0333-01-F1 PCB. So far these conversions have ONLY been seen on 0333-03 PCBs.

the PAL modification is different here are the modifications:

PCB 0333-01-F1
-Remove U19
-Remove U4 pin 3, 20, and 21 from socket
-Jump U4 socket pin 2 to socket pin 20
-Jump U4 IC pin 3 to U4 IC pin 24
-Jump u18 pin 31 to 32

Then... replace the Roms/provide 3.3V power to SMD ROMs like you do on the other conversion
 
xodaraP said:
So this was on a standard KoV2 cart? Nice
Click to expand...
yes.

I don't think the game matters so much as the PCB number... it's just that normal KOV2 carts tend to run on an earlier PCB revision from Nine-Dragons, which has a different layout and a different PAL... so the modifications to the PAL are different. I'm going to try my same methodology on another cart revision tomorrow.
 
If it is just a difference in how the PAL needs to be modified, does that mean you now know how that modification works and could apply the same method to work out the modifications required for other donor carts?

Asking for a friend :whistling: :saint:
 
twistedsymphony said:
I was able to successfully get Espgaluda running on my non-Nine Dragons KOV2 cart #0333-01-F1 PCB. So far these conversions have ONLY been seen on 0333-03 PCBs.

the PAL modification is different here are the modifications:

PCB 0333-01-F1
-Remove U19
-Remove U4 pin 3, 20, and 21 from socket
-Jump U4 socket pin 2 to socket pin 20
-Jump U4 IC pin 3 to U4 IC pin 24
-Jump u18 pin 31 to 32

Then... replace the Roms/provide 3.3V power to SMD ROMs like you do on the other conversion
Click to expand...
I attempted this on a 0333-00 which looks absolutely identical to a 01 but I'm greeted to a garbled green and purple screen. There must be some very slight differences between the revisions.
 
kuze said:
Right it's xor'ed against a key, anyways to decrypt or encrypt works the same way.
Click to expand...
I'm such a dumbass, 1FFFFF is ofcourse not the same as 200000.
Yes, i was dumping clear code but the size was wrong. This causes my screwup.

The good news is, i can unpack and repack the code now.
And there's 27c322s in the UV eraser.
Maybe a dual rom in an hour. Maybe not. We'll see.
(This completes my christmas effort if it works, i usually release something around christmas..)
 
Asure said:
Good news. It works in MAME.
Bad news: Cart is detected and boots in a real motherboard, but crashes when the selection screen appears (Illegal Instruction)
Click to expand...
You can upload the rom and some photos about the selection screen， rom error？
 
Sure, here's the screenshot:

instruction.png

Rom is just too big to attach. It does not compress very well.
Try this
https://wetransfer.com/downloads/03...load_button&utm_source=notify_recipient_email
 
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