Author Topic: MiWi2 (VT168) Dumping Attempt  (Read 5839 times)

forgotusername

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MiWi2 (VT168) Dumping Attempt
« Reply #15 on: December 19, 2017, 06:21:47 PM »
I'm not familiar with the technicals of this stuff, but by "fake cartridges" do you mean those GBA-shaped things that have no guts inside them, but trigger games for the system they came with?

Oh, and if you're investigating this stuff you might wanna look into this console called the Lexibook 300-in-1. There seems to be a hidden SD card in the system with VT368, VT09 and regular NES ROMs stored on it. I opened the system up but its pretty deep in there, behind literal layers of screws and I didn't wanna break the console just to get out potentially nothing.

davidstech

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MiWi2 (VT168) Dumping Attempt
« Reply #16 on: December 19, 2017, 06:50:47 PM »
Yes, that's what I mean by fake cart.

The Lexibook console with ROMs inside sounds awesome, any chance you could send me the suspected VT368 ones? If not don't worry as I'll probably get one myself out of curiosity in the inevitable post Christmas sale on those sorts of things.

Y2K05

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MiWi2 (VT168) Dumping Attempt
« Reply #17 on: December 19, 2017, 09:18:14 PM »
I think i may have heard of it. Why would they load roms on a microSD though? Lazy shortcut? Additionally, which console is this? Is it this one: https://www.amazon.co.uk/Lexibook-JG7800-300-Retro-Console/dp/B072F6ZWJP ?
« Last Edit: December 19, 2017, 09:24:48 PM by Y2K05 »

forgotusername

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MiWi2 (VT168) Dumping Attempt
« Reply #18 on: December 20, 2017, 01:58:57 AM »
davidstech
Dec 19 2017, 06:50:47 PM
Yes, that's what I mean by fake cart.

The Lexibook console with ROMs inside sounds awesome, any chance you could send me the suspected VT368 ones? If not don't worry as I'll probably get one myself out of curiosity in the inevitable post Christmas sale on those sorts of things. [/quote]What I'm trying to say is I can't get the SD card out without potentially breaking the system, which I don't want to do as its a really nice lineup of games. I should also add the circuit board had text printed on it, and in addition to saying the operating system is VT368, there's a SD card marking on the back. But that's as much info as I can give.

Quote:
 
I think i may have heard of it. Why would they load roms on a microSD though? Lazy shortcut? Additionally, which console is this? Is it this one: https://www.amazon.co.uk/Lexibook-JG7800-300-Retro-Console/dp/B072F6ZWJP ?[/quote]Yes that's the console, but...that listing says it has an SD card, even though its hidden in the plastic...I guess the European version has it accessible? Mine came from a Toys R Us in the US, so I guess the American version hid it since it would undoubtedly be used to load NES games. It also was WAY cheaper; the UK version is $25 more. Weird.

davidstech

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MiWi2 (VT168) Dumping Attempt
« Reply #19 on: December 20, 2017, 04:03:01 AM »
No worries, I'll probably get one myself as it will would be a useful development platform for testing code if there are ever ambiguities as to what the hardware should be doing.

Although the listing mentions an SD card the Q&A after it says it doesn't have one so I'm not sure what's going on. Perhaps it was removed at the last minute.

It's also interesting - and helpful - that they silkscreened the part number onto the board as none of the systems I have had have that.

Assuming it can run NES and VT03 ROMs that raises interesting thoughts about the architecture of the VT368, and confirms speculation that unlike the VT168 and VT268 it is also backwards compatible with the NES, and must have a mode where NES style sound and video hardware are accessible in the right place.

forgotusername

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MiWi2 (VT168) Dumping Attempt
« Reply #20 on: January 15, 2018, 06:13:58 PM »
Thought I'd make an update that I finally digged into the 300-in-1 thing and it does NOT have an SD card slot, just a marking of where one presumably was in development. I also got the operating number wrong (don't blame me, the text is tiny) - its VT389, something I didn't know even existed.

If its useful to anyone the full operating thing on the back says:

GB-N013-Key-VT389-1
REV:A2   2Z
2017.03.24

Wonder if GB means Game Boy. It looks nothing like Game Boy/Advance hardware, but considering all the insane stuff derived from NES hardware who knows.

davidstech

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MiWi2 (VT168) Dumping Attempt
« Reply #21 on: January 15, 2018, 07:27:54 PM »
If it's still apart, would you be OK posting some photos of the inside and what chips you can see?

forgotusername

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MiWi2 (VT168) Dumping Attempt
« Reply #22 on: January 15, 2018, 08:20:42 PM »
davidstech
Jan 15 2018, 07:27:54 PM
If it's still apart, would you be OK posting some photos of the inside and what chips you can see? [/quote]Sorry, I already put it back; but there was literally nothing in there besides a globtop chip. There were plenty of small boards connected to the main one by wires (all of which had the exact same model number on them), but they were all for buttons and connectors (power, reset, video cables, power cord). In addition there was the deceiving marking of where an SD card would go, but with no electronics even near it.

The only other technical thing I noticed was on the system, the game select menu is a larger resolution then the games (can't tell if that's the special 512x480 resolution or not). But that's all the info I can give.

codeman38

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MiWi2 (VT168) Dumping Attempt
« Reply #23 on: March 13, 2018, 01:22:19 PM »
On a whim, I tried importing the MiWi Arcade Games ROM into Audacity as unsigned 8-bit audio to see if I could find any recognizable tunes, since that's worked for other Famiclone consoles with sampled audio. It looks like the audio clips are encoded at ~4200 Hz, and I can clearly recognize one of the menu themes (the one from the 16-in-1 menu screen with the electric piano arpeggios) at 0x56000, but it's very fuzzy and garbled.

Is there some kind of bitwise manipulation going on with the music as well? Several of the audio clips are surrounded by long strings of 0xEA bytes, which seems suspicious in that respect, but if so, I'm not sure what the correct transformation is. (Or am I possibly using the wrong codec entirely, despite unsigned 8-bit PCM producing an identifiable melody?)

Edit: Probably some kind of DPCM codec, most likely. Interpreting the audio as a Famicom DMC sample at ~34KHz, the melody is at the right pitch and even more clearly identifiable, but it's still scratchy.
« Last Edit: March 13, 2018, 02:53:34 PM by codeman38 »