NEX just arrived, time to take it apart!

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NEX just arrived, time to take it apart!

Post by Guest » Thu Oct 27, 2005 2:01 pm

Unfortunately all the chips inside are globtops except for the ram. Looks like there are two separate chips for the cpu and ppu but no markings. Very compact inside with the wireless/audio/video taking up about as much space as the power/cpu board.

I would say video quality is in between front loader RF and RCA. Good colors but lots of smearing. Also some artifacts from the last row of pixels of white text on SMB1, could be something with the scrolling switch.

Audio seems higher pitched, collecting coins in SMB1 sounds different. There is stereo audio coming out of the box but no information on their website about how to program for it.

Wireless can be turned on/off from a switch on the side, has to be off to use Four Score which fits well in the ports. There are also "Charging Ports" in the back to charge the wireless controllers(?).

Havent tested many games yet, any good suggestions?

Jagasian
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Post by Jagasian » Thu Oct 27, 2005 7:04 pm

I'd suggest testing every game that is known to have problems with other clones and emulators. Check out this review of the Yobo NES clone for some games that have issues:
http://www.atariage.com/forums/index.ph ... opic=67476

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Post by bunnyboy » Fri Oct 28, 2005 12:49 pm

I was surprised at the incompatibilities of this many games. My collection is not yet complete so here are the games from the previous link that I was able to test:

After Burner - garbage on screen
Castlevania 3 - dark green screen
Gauntlet (licensed) - minty green screen
Gemfire - solid black screen
Laser Invasion - minty green screen
Rad Racer II - complete hardware freakout, no power light

All carts played fine on USA front loader. I think the minty green screen is their version of the gray NES screen. Adding a game genie did not help any of the games.

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Post by Great Hierophant » Fri Oct 28, 2005 3:11 pm

The Neo-Fami I tested did better than that. It was able to show the opening of Castlevania 3 (but hung) and start up Gauntlet and Rad Racer (but the graphics glitches made those games unplayable.) Try a few Codemasters games for some incompatible fun. It just goes to show that it takes a truly serious effort to replicate any console.

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dXtr
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Post by dXtr » Fri Oct 28, 2005 3:38 pm

I actually had some hope in this machine.. but from what I can read here it sounds like this is YACF (Yet Another Crapy Famiclone :P)
Sorry for misspellings, I'm from Sweden ^^

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kevtris
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Post by kevtris » Sat Oct 29, 2005 10:28 am

bunnyboy wrote:I was surprised at the incompatibilities of this many games. My collection is not yet complete so here are the games from the previous link that I was able to test:

After Burner - garbage on screen
Castlevania 3 - dark green screen
Gauntlet (licensed) - minty green screen
Gemfire - solid black screen
Laser Invasion - minty green screen
Rad Racer II - complete hardware freakout, no power light

All carts played fine on USA front loader. I think the minty green screen is their version of the gray NES screen. Adding a game genie did not help any of the games.
Yeah, sounds like they didn't hook the "CIRAM /CE" line up and PPU /A13 to the cart port, but instead connected those internally. They must not have known you had to do this for NES carts (though you still do for fami carts).

This would prevent 4 screen games working, and it would prevent Afterburner working, 'cause afterburner disables it to do hardware nametables for the tile animation they do. So that explains Gauntlet, Rad Racer (4 screen) and afterburner (HW nametables). The other carts are MMC5, so the MMC5 is probably freaking out 'cause it has to synch with the PPU somehow to do i.e. IRQs. Soo, I'm guessing without that line on the cart, the PPU can't synch up, so it will not perform interrupts. Without this, some games may start, but will crash or hang without interrupts.

It might be possible to go inside the case and wire these 2 pins up to the NES on a chip in there to fix it. I'd have to see a pic of the guts though. Anyone wanna take a picture and post it somewhere? (note: should be fairly high resolution so I can see details).
/* this is a comment */

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Post by Great Hierophant » Sat Oct 29, 2005 11:40 am

What morons! How much would it have cost them to send two more lines to the cartridge port? Maybe instead of assuming that no cartridge used the lines, they should have tried connecting them when they were testing these cartridges, if they ever tested them at all.
Yeah, sounds like they didn't hook the "CIRAM /CE" line up and PPU /A13 to the cart port, but instead connected those internally. They must not have known you had to do this for NES carts (though you still do for fami carts).
If they hooked the lines to the Famicom connector, then it is likely that these games would work if connected to a 60-72 Pin Converter, like the sort Lik Sang sell. How ironic would that be?

Guest

Post by Guest » Sat Oct 29, 2005 2:22 pm

Yeah, I'm not a hardware guru, but this system sucks. I just tried playing SMB3 and Kirby.

SMB3: Some sounds pitches are way off. Mario's jump is a lot lower, etc.

Kirby: The DPCM channels are overdriven and whenever they are active, the other channels are quiet.

Overall, it seems to be crap. :(

Guess I'll ship it back.

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Post by Jagasian » Sun Oct 30, 2005 12:16 pm

Check out this thread at DigitPress. People have been posting compatibility issues, impressions, etc of the system. As well as participating in an on-going dispute over how Messiah mislead people with regards to the NEX and not being up front about incompatibility issues. DreamTR posted an official link, finally, listing compatibility with NES games. Note that even if a game has significant graphical glitches when played on a NEX, it is still listed as working :? I guess they've gotta keep that compatibility percentile inflated?

I called shenanigans when they wouldn't comment on whether a game was compatible or not, even when they started taking pre-orders and shipping the system. Compare this to kevtris's FPGA NES, where he is very open about what does work correctly and what has issues. They should have paid kevtris to design a proper clone :wink: Maybe they will make a NEX 2.0, ala the Flashback 2.0, and next time around not base the system on a shite NOAC. (yes I will keep dreaming)

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Post by teaguecl » Mon Oct 31, 2005 9:47 am

Any chance of posting some pics of the inside of this thing?

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Post by bunnyboy » Mon Oct 31, 2005 10:18 am

I can get some (hopefully) high res picts of the boards tonight, and trace where the ciram/ce and ppu/a13 lines from the nes cart connector go to. Will also be making a schematic of the video circuits to compare to design of the various nes versions.

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Post by drk421 » Mon Oct 31, 2005 6:59 pm

Maybe they should've hired kevtris?

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Post by bunnyboy » Tue Nov 01, 2005 3:32 am

Pictures of the board are available at http://www.retrousb.com/NEX/NEX.html Big chips are labelled on one of the pictures, CPU and PPU are labeled where they appear. Pictures probably arent high res enough to do signal traces.

While checking out the connections I noticed some of the famicom port pins are not correct according to http://nesdev.com/fam_pinout.txt Mainly pin 16 isnt connected to ground, and pins 45/46 arent connected to each other. Dont know if that will affect any games...

The PPU /A13 on the NES connector is wired to the PPU glob and also to the wireless board and labelled as "mode". Used as a clock signal?

The CIRAM /CE pin on the NES connector is connected to a ground plane on the main board. The CIRAM /CE pin on the Famicom connector is connected to the same ground plane. I suspected the problem with Rad Racer II was a short somewhere, which is confirmed because it connects CIRAM /CE directly to power and the NEX connects it directly to ground. Cutting the wire makes Rad Racer II display a green screen instead of no power light. The NEX uses only one sram chip for wram and vram, with the /CS line as an output of some lsi logic. Separating the CPU and PPU sram control lines should show where to reconnect the cart CIRAM /CE, but that will take more signal tracing on another day...

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Post by leonk » Tue Nov 01, 2005 8:28 am

WOW.. thanks for those pics.

Anyone noticed the date on the PCB? Sep 20/2005. Massiah wasn't planning on shipping this thing earlier as stated with such a late manufacturing date. :(

Also, can you trace the video path? I'd be interested to see how they designed the video amp (going from video out on PPU all the way to the RCA jack).

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Post by Quietust » Tue Nov 01, 2005 12:55 pm

bunnyboy wrote:While checking out the connections I noticed some of the famicom port pins are not correct according to http://nesdev.com/fam_pinout.txt Mainly pin 16 isnt connected to ground, and pins 45/46 arent connected to each other. Dont know if that will affect any games...
Pins 45 and 46 are Audio IN/OUT - on most cartridges, these lines get tied together, but on MMC5/VRC6/Namco106/etc. cartridges, both of these lines go to the mapper. As for pin 16, the official Famicom schematic lists this pin as GND, so I'm not sure what's going on with this one...
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P.S. If you don't get this note, let me know and I'll write you another.

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