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PostPosted: Mon Apr 17, 2017 2:08 am 
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Hi i have a nevir mastergames nvr-vi(in spain) also know as milmar top loader in brasil. I opened It to repare the lm chip and i take a look to motherboard.

I view the motherboard is diferent to other boards i view surfing the web.

-He have two diferent conectors to power/vídeo board. One in the upper part and other in left part.(there is another famiclone with that?).

-He have a led not fitted, and unkown ic not fitted.
-He have a site to other xtal, and some elements not fitted.And a select switch not fitted.

What other configuration can support this motherboard from Factory? Is any other know famiclone using this board?.


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PostPosted: Mon Apr 17, 2017 11:16 am 
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Without a picture of the underside of the board, it's very hard to guess what the other things are doing here.

XTAL2 connects to a variable capacitor ... and we have no idea what either end of that is doing.

U7 has no obvious connections to anything at all.


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PostPosted: Mon Apr 17, 2017 3:39 pm 
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No problem :)


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PostPosted: Mon Apr 17, 2017 4:13 pm 
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XTAL1 and XTAL2 are two different kinds of oscillator topologies, designed for a "parallel cut" vs "series cut" crystal.

U7 ... hard to say. Clearly involved with both the SELEC header and the VR1 potentiometer.

Pins 14, 13, 12 are +5V; pins 10 and 1 are shorted together (and go to the SELEC header); pin 9 goes to one side of the potentiometer; pins 8, 4, and 2 are shorted together (and go to the other side of the potentiometer); 7 is ground; 6 goes to the other side of the SELEC header; and pins 5 and 3 are shorted. Vaguely looks like a 4000 and 7400 series part (given no interesting power supply and location of power and ground) but nothing obvious, given how it's connected.


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PostPosted: Tue Apr 18, 2017 4:01 am 
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Yeah, is rarely constructed even the pads not match the typical famiclone pads pinout. I folow the wires from pad and all are located in the 5 pin of the upper db9 line. But i not sure Who is Who in pinout.

For the database these are pictures of the console. In spain are comercialized three models the red with turbografx clone pads as the Brasil versión(made in Taiwán) and the black with others big pads mande in china),the other is very rare and is black with infrared pads.

All are socketed as i know and all uses discrete ics. Never is released with noac. The motherboard is from the red.


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PostPosted: Tue Apr 18, 2017 4:58 am 
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First time I see that the symmetry between CPU and its peripherals and PPU and its peripherals shown even on the PCB ;)


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PostPosted: Tue Apr 18, 2017 11:41 am 
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tic wrote:
Yeah, is rarely constructed even the pads not match the typical famiclone pads pinout. I folow the wires from pad and all are located in the 5 pin of the upper db9 line. But i not sure Who is Who in pinout.
Tracing the pictures, it seems to match the variant that randomly made it to the wiki, at least for DE9 pins 2-4.

The missing R17, R18, C27 are also interesting; I think those are an interface for the microphone that was the HVC-001 player 2 controller.

When I look closer at the exact connectivity of U8 and U9 ... it appears to be exactly identical to the canonical leaked Famicom schematic ( http://nesdev.com/Ntd_8bit.jpg )

... OH. Right, you're in Brazil. U7 is something for doing PAL-M transcoding, like this thing that Fisher has shared. I assume "SELEC" would toggle between PAL-M and NTSC encoding ... so I bet I was wrong; the two crystal places are for a 21.477MHz crystal for NTSC and a 21.454MHz crystal for PAL-M.


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PostPosted: Tue Apr 18, 2017 2:35 pm 
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Interesting guys thanks, no, i am in Spain, the nevir was released here in early 90/91/92 i think. The Brasil version was released in 1994 i read un brazilian pages.

If anyone can post the output pins of the db9. Can be very hepful,i need pads for de red console.

I view also the made in taiwán here have two sub variants un serial number, one begining in 000xxx and another begin with 280xxxx

Here is pal-B the nevir.

I think should be sold in taiwan probably with another variant. Nevir(today continues). Always rebrand , one day they made a portatil dvd with screen. Well the screen was the original screen of psone!. They put a adhesive in the PlayStation logo!.

This is the pad:

Wire colour(from right to left looking pad connector ).

Conector para db9 (left to right).

Rojo:pin 5 Up (ground)?.
Naranja:pin 1 up (VCC)?
Blanco:pin 3 Up (latch)?
Azul:pin 4 up ( data)?
Negro: pin 2 Up (clock)?

O.k so reverse 2,4


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Last edited by tic on Tue Apr 18, 2017 2:52 pm, edited 2 times in total.
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PostPosted: Tue Apr 18, 2017 2:41 pm 
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Tracing the photo, DE9 pins 2-4 are the same as the convention mentioned on this random page on the wiki


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PostPosted: Wed Apr 19, 2017 3:34 am 
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Can be some part no fitted related to infrarred pads?. I found a picture of another model in the web, It appear became with the box with double system write in inglish and without gun drawed in. The box is from begining 92 end 91.

Take a look at front photo they have a some time of infrarred led or is the led of the board?.

http://www.todocoleccion.net/videojuego ... ~x53078161


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PostPosted: Wed Apr 19, 2017 4:21 am 
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Interesting.
I found that the name of this clone in Brazil is (was) Top System, not Top Loader.
I have no idea of how it's guts are...
Attachment:
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PostPosted: Wed Apr 19, 2017 4:39 am 
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Yeah, my error top system, But i not have found picture of the board. :(.

I try found and buy here another with the led/infrarred in the front to take pictures of PCB, But they are very rare, i think was the first version released here. Normally all are the box with mame in spanish and the gun draw in box


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PostPosted: Wed Apr 19, 2017 6:31 am 
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An old friend of mine once had one of this.
I'll try to find and ask him.
Unfortunatelly, it was about 15 or 20 years ago, and I'm really not sure if he still has the console.
I'm very curious about these old NES clones!!


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PostPosted: Wed Apr 19, 2017 10:57 am 
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tic wrote:
Can be some part no fitted related to infrarred pads?. I found a picture of another model in the web, It appear became with the box with double system write in inglish and without gun drawed in. The box is from begining 92 end 91.

Take a look at front photo they have a some time of infrarred led or is the led of the board?.
You're referring to this picture? http://cloud10.todocoleccion.online/tc/ ... 030731.jpg

I haven't the foggiest idea what that could be. I don't see anything on the PCB you've shared that would make sense to connect with an LED or photodiode.

The PPU's Vblank NMI output appears goes to two places on the mystery IC (the upper pad on the SELEC header; pin 6 on the 14-pin footprint). I have absolutely no idea what a 50Hz signal would be useful for here...


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PostPosted: Wed Apr 19, 2017 12:33 pm 
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Yeah exactly that picture. But do you have view the left down corner of the board in front? Is marked as "led" :).

I know there is a another variant with ir:


https://goo.gl/images/PjvwzV


http://www.todocoleccion.net/videojuego ... ~x52398038


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