1989 famicom with true rgb, s-video, stereo sound

Basically this's all stuff I've done before but for the first time with an original famicom.

Early pics:





Mostly finished video:

http://www.youtube.com/watch?v=RdB36eghRJc&feature=youtu.be

What's left to do: Build all the external ports and jacks into a project box.

Why I built this: I had the parts laying around and I thought it would be fun!

Specs:

This started out as an official nintendo 1989 famicom that I recently managed to repair (some random trace got damaged).

This system using an official nintendo rgb chip and produces almost completely jailbar free true rgb, s-video, and stereo sound with proper mixing and amping.

S-video is generated by a sony cxa2075 video encoder which produces the sharpest looking s-video I've ever seen, also I really like the colour encoding of the cxa2075.

I built a small circuit that divides the system master clock down to be able to drive the video encoder which removes colour bleeding over s-video.

You can realtime switch between the default and upgraded audio circuits using a hardware switch I installed.

I hardwired nes controller ports into the headers of where the famicom controllers normally connect, here's the schematic:



P4 is player one and P5 is player two. Just do the same thing for p5 to wire up the second player controller (ignore the mic pin for nes controller port wiring). This nes controller port wiring is 100% compatible with all games, some people wired up nes controller ports to the famicom expansion port but that doesn't work with some games (mario 2 us). My wiring works with everything and you no longer need to live with stupid hardwired famicom controllers where the cord comes out the side of the controller instead of the top like it should.

The 74ls373n has been removed with a precision socket installed so I dropped in a 74hc373 to get the powerpak running with the rgb setup. Thanks to acem77 for making this discovery. The playchoice pcb uses the 74hc373, that's where the nes compatible rgb chip comes from so I guess it's just something the rgb ppu needs.

The rf box has been removed and I have the system running using just a power jack, 7805 regulator, small heatsink, and a fuse. The 7805 and heatsink are bolted near the front of the case to make room for the added circuitry at the back.

What I learned from building this:

I learned a lot about the famicom pcb and how it's wired. The edge of the pcb is 5v so be careful not to think it's ground like most consoles. The connector for the rf box is interesting, one pin is the 5v fed from the regulator, the other pin is the 5v feeding back into the rf box circuit after you connect it using the power switch.

Adding distance between the ppu and the video encoder adds jailbars. Adding 5 or so inches of distance for the rgb to travel before hitting the video encoder added really big jailbars. Potentially this's a universal jailbar fix across all models of the nes / famicom which is fantastic news! Having the ppu signals fed into the video encoder at point blank range completely fixed the jailbars on this system. This's an awesome discovery! Unfortunately this means that getting rid of jailbars in some pcb revisions means relocating the entire ppu socket to get all this custom circuitry to fit like I had to do with this system.

This particular famicom (something-something-gpm-02) has a very similar audio circuit to the av famicom. The only difference is there's a little more low pass filtering with this model producing more bass and a little more muffle.

The famicom case has literally no extra space inside to fit any extra stuff which is why all the added ports and whatnot are hanging out the back.

Would I do this again?: Probably not unless someone is willing to pay a small fortune or if I somehow kill my system (it has a fuse so if something shorts it's easy to fix). I had to relocate the entire ppu socket to the back by wiring up 40 ide wires, I had to do so much extra work that it would be cheaper just buying an av famicom.

Was it fun making this?: F#ck yes! The results were fantastic, I learned so much about these systems and getting rid of jailbars and other video interference from doing this, wiring the nes controller ports worked out great too. The audio circuit on this kit I use sounds great with this pcb model, hopefully someday I can rework the av famicom audio circuit so I can re-create it on any model of the nes / famicom. I honestly didn't expect this to turn out so nicely.

I think this was pointed out already, but any NES or Famicom cannot have any kind of "stereo sound" and never will. The console was designed to be mono. Separating bass and trebles and send each one to each speaker is NOT "true stereo sound".

RGB and S-video can be a nice to have though, even if I don't personally care.

The two NES controller ports support 4 player games, right?

For a device with NES controller ports, you'd need a Four Score. It works by sending the first 8 bits from controller 1 or 2 on D0, then the first 8 bits from controller 3 or 4 on D0, then a signature byte on D0. I don't see any reason why it wouldn't work, as it just uses the clock, D0 out, and D0 in wires, unlike the Famicom expansion controllers that use D1 in. However, you would have to use games compatible with the Four Score; Japanese versions of 4-player games might assume Famicom expansion controllers.

As for comparisons between the Four Score and stereo sound, the SPI-like bit-serial protocol allows the program to tell the difference between the controllers through the sequence: it's always 1, then 3, then signature on $4016, or 2, then 4, then signature on $4017. Audio, on the other hand, is summed before being sent to the APU's audio output pins.

This... "Stereo" in this scenario is anything but an upgrade.
Otherwise, good work on the video encoding.

Haha thanks. I set my amp to mono so I don't get any stereo separation. I just like the circuit because it balances everything great including carts with audio chips. I havn't tested it with any peripherals just regular nes controllers.

*edit*

pic of the pcb:

No, it doesn't "balance everything great". I will repeat the same thing that has already been said by others: you do not get stereo, or anything even close to it, with this modification. Instead, what you get is crap-sounding audio where both square channels come out either the left or right speaker (your choice), and the triangle/noise/PCM channel comes out the other (see pins AD1 and AD2). The end result is crap; it sounds absolutely awful solely because all the audio on NES/Famicom games was mixed/intended to be heard in mono. The composers/musicians actually sequenced and designed their music with that in mind. Honest.

As far as expansion/audio chips (as in VRC6, etc.) go -- those output all their audio to a single pin (see pin 45). No resistor array possible (for "splitting" frequency ranges) will turn that into stereo -- all it will put out is "split" audio which has the same problem as I mentioned above.

The video modifications you've done are really great though, as others have also said. Kudos!

Yeah, this stereo mod is in the realm of enhancements, things which bring out some quality at a cost to others, and are subjectively either improvements or detriments. The stereo mod is interesting because it's able to recover some information that is otherwise lost in the mono output, that of separating the channels into two sets. It reminds me of the old 4-channel mods on Amiga computers, where each side had two channels, totally separated. It's unnatural sounding. A stereo mod that mostly mixed them, with only slight separation, might be more pleasing. One thing I noticed is that if you tap into the separate channel groups, you must attenuate one, otherwise it's a lot louder than it should be. The mono mixdown in the NES does this (look at the differing resistors used for the two groups).

Haha, original 4-channel Amiga MODs (i.e. "M.K." format), which also had the awesome design of the individual channels being set to L/R/R/L. I still want to know what the reason for that is, in other words, why LRRL and not LRLR. I'd love to ask Karsten Obarski or Michael Kleps what the reasoning was.

I wasn't talking about stereo separation I meant bass, treble, and mixing of the audio in certain carts. I already said I play with my amp set to mono I don't experience any stereo separation. It's really easy just to set your amp to mono if you don't like it. And thanks for the compliment! I wish I knew more about designing audio circuits, I've gotten s-video pretty perfected in every console, now I gotta learn how to design audio stuff for my favourite consoles.

Done:



video:

http://www.youtube.com/watch?v=wkdapA2xx0o&feature=youtu.be

Good stuff! It's a Famicom choo-choo train!

Two thoughts: 1- it's really sad that you can't genlock your camera to the FC; I find the rolling bars distracting.
2- That's an awful lot of hot glue inside—if anything ever goes wrong it'll be hard to fix it.

Where does the expansion audio go in the dual mono mix?

Sorry about the camera I don't think it has that setting. The glue is very easy to get off I've fixed many things with just as much hot glue. Actually I had something break because it wasn't glued into place, so I repaired it, glued it, and now it's fine.

With the dual audio circuit the expansion audio pins (45 and 46) are disconnected from the famicom pcb and routed into the audio circuit. The audio circuit is a couple of opamps, a virtual ground, some inductors, and a network of resistors and caps.

Hot glue is great because it does a good job of holding projects together, but if you need to do work a little isopropyl alcohol will do the job to remove it.

Finally someone who gets it. I actually just heat up the glue with a soldering iron and remove it with some tweezers it takes me like a whole 2 seconds. I've met plenty of people online who had their stuff break because a wire that wasn't glued down snapped off and either they weren't able to resolder the wire or it shorted something and bricked the system.

The worst is when the pad gets ripped up.

I'll have to disagree. If someone needs to use so much glue to secure something then he needs to reconsider his modding/assembling/soldering methods. So much glue is only found on very cheap electronics and is used just for what you say here: to hold the thing together.
At any rate, each one has his methods and way of thinking , you can't argue with something that works ...

Professionally made products often don't need anything like hot glue (which isn't even really a glue) because integrated into the product is some form of strain relief; for example, an NES controller has the cord inside go around several plastic posts before leaving the case. In the case of a modification, these aren't present. No matter how good your soldering is, if you have a few wires soldered to some scraped-up traces of copper and you yank the wires, it's not going to be lovely. You should never rely on soldering for anything remotely structural.

A controller cord is a way too different case than internal cabling in a console. That internal cabling does not receive any kind of stress , something that is expected from a controller.
Even in the controller case though, hot glue is not the best option since like you said it's not really a glue. You are way better with a cable knot inside the controller than any amount of hot glue.
Hot glue is useful to hold things in place , in small doses and in places that does not get in the way of repairs or replacements. In no way soldering is to be treated as permanent fixing or glue as solder replacement.
I hope it's clearer now what I mean.

Tell that to anybody who has ever tripped over a controller cable. There's a reason that Xbox and Xbox 360 controllers have an inline release.

I think this is the reason:



No one wants an XBOX console landing on their kid's head. Especially Microsoft.

so according to you, the cabling of the rgb mod are likely to sustain the same stress as the famicom's controller cable?
and btw, here are the internals of a wired 360 controller:



the only cable is the cable that connects to to system and naturally it is molded to absorb shocks before it reaches the pcb, no one argues with the success of this solution. I still don't see how the controller cable is related to internal cabling , unless you believe that if the pcb was covered in hot glue it would react better to shocks?

I see absolutely nothing about that cable that indicates its "moulded to absorb shocks", because you chose to post a picture of the wrong side of the PCB. The grey rubber used at the ingress point where the cable meets the plastic shell of the controller is not for relieving pull stress; it's for relieving tension induced by cable bending (left/right or up/down). That rubber moulding and the plastic shell of the controller will not withstand pull stress.

Here's a much more relevant picture:

http://hothardware.com/newsimages/Item8 ... roller.jpg

Note that the wires in the cable go to a socketable connector ("white thing") that's on the PCB. If you pull really, really hard on this cable (and assuming it wasn't connected via USB; i.e. let's pretend the cable is soldered right on to a PCB inside of the console, such that the cable is not detachable), I can assure you that connector on the PCB, and/or the wiring, will tear itself loose.

This is one of the main reasons why Nintendo made the NES controllers socketable (vs. being hard-wired like the Famicom), and why every console made since then has used sockets as well; kids and human beings trip over them all the time. Do you know how many people I personally know who have had their laptops destroyed as a result of their children or pets running through the house while the AC adapter was plugged in, yanking the laptop off the table? Why is Apple's magnetic power AC power connector (MagSafe) so popular (barring the L-shaped one, which is an engineering design mistake from hell; the 1st and 2nd-gen connectors are engineered properly)? Surely it must be bullshit, right? :-)

so I am supposed to somehow believe that the molded cable INSIDE THE RED SQUARE , is not supposed to absorb cable shocks such as pulling ?

here, I'm gonna use your picture because mine apparently "indicates nothing" for the cable and we also need to see what's after the mold for some reason:



That mold "secures" with the controllers frame, in order to pull and rip off the connector inside you will have to actually break the controller's frame where said mold nests and then the cable will pull the connector with it. Believe it or not that's it's primary function. If there wasn't such a mold then you would have some sort of zig-zag mechanism going inside that would absorb pulling - like the famicom or even ps1/2 pads. The same mold can be seen in almost every factory made appliance.

in fact, let me break it down to you with a dvd player that I happen to repair atm and it's power cable (that is the same basic design as your 360 controller one)
Here is where it nests (metal dvd frame = controller frame)



and here is a breakdown of the mold on the cable and what are it's uses:



on the red square you have the same "pulling protection" since if you try to pull the cable the metal frame will absorb it
on the green square you have your protection against "relieving tension induced by cable bending (left/right or up/down)"

back on the 360 wired controller you can see in green the bending relieving mechanism and in red the pulling protection and where it secures on the pastic frame (and in extend you 360 controller picture is not that relevant since it actually misses the bending protection stuff)




I don't get it at all, are you trying to explain me this in other words? Can you also pinpoint me the part where I said that soldering cables is secure and you can wank them all you want?
It all begun with a fail comparison of internal cabling with a controller cable and now I am wondering if my English is so bad that somehow I don't get you people to understand what my point is.

Once again, a gazillion hot glue inside this rgb mod offers NOTHING, it does not secure anything and it just makes afterwork harder. Those cables (of the rgb mod) DO NOT suffer any kind of stress. They just needed a small amount of glue to keep them in place and nothing more. That's of course MY HUMBLE OPINION and I have said that in my very first post here.
Then someone started talking about controller cables and I replied that instead of using hotglue to secure the cable in the controller it is better to tie a knot with it and have it inside the controller's frame so you cannot rip it off easily. Hot glue does not secure a cable. The knot inside will protect the connections when pulling whereas hot glue will just break after some force is applied. This knot "technique" is too old and cheap and is widely used in stuff that need to have some cable pulling protection and they use plain standard cables.
Here is an example:



the knot is used as protection from pulling, if anyone thinks that the same level of protection can be achieved by any amount of hot glue then I have nothing more to say.

Hot glue in huge amounts is used in cheap stuff to hold the whole thing together. One can use it as he wants , noone argues with that but other opinions do exist.

Anyway, that's the last thing I have to say on the subject, I already wrote too much and it's way OT at this point.
Not trying to start a flame war btw, just re-writting my thoughts and with greater detail (hopefully)

I don't understand, you suggest I knot all 40 ide wires connecting my remote ppu socket instead of just gluing them into place? Anyway modded consoles usually go through a lot of tinkering (opening up and removing the circuit to change things) since people find circuit improvements. I've found plenty of people online who tinkered with their modded console and then it broke because something snapped off.

Is your famicom a controller? is your mod a controller cable? in what part exactly I am suggesting to use knots on your rgb mod?
What I am suggesting was to solder your cables in their place and use a little glue to keep them from moving, nothing more - nothing less.
If you solder your rgb cables correctly they won't just snap off, having cold solders and relying on hot glue so your work won't snap off is a bad idea.



and that's why you DON"T NEED to use so much hot glue. Your mods become inaccessible. You need to remove the glue, risking lifting a pad/track and all that in vain since that much glue on this particular area is really useless unless you want to play football with the pcb and need to secure it in a mass of glue or something.


Anyway I'm done with the subject for real this time, when people understand that they need to use the knot trick on an rgb mod then it's a sign that I really can't write comprehensible things

Cool, you chose to post a picture of a XIM2 Edit: better link: http://www.youtube.com/watch?v=YOdEmBZbd0s
Edit: koitsu's picture.

I've gotten really efficient at removing hot glue, it's really not in my way when I need to redo something.

When pulling directly (vs. side-to-side), yes.


No, it's not. The primary function is to resist stress on the white plastic connector / soldering points inside when the cord is moved left/right or up/down, and the secondary function is to resist pull stress -- and it does the latter very, very badly.


The "zig-zag" method, re: cables "routed" around plastic posts used to hold screws, also does not work reliably, usually because the plastic moulding of the controller and the underlying screw holes is very soft.


This has the same problem as the wired Xbox 360 controller I linked. In fact, what you're showing is even worse -- this would break loose with very little pull tension; the 360 controller would withstand more, but only a slight bit more.

Look at the pictures. Surely you can see what the problem is, no? I don't think it takes a physics major to figure this one out. On the 360 controller, the issue is that the depth of the groove in the rubber (which the plastic shell of the controller goes into, thus "preventing stress") is not deep enough. It must be as deep as possible, because all the tension/stress is going to end up there when pulling.

On your DVD player, it's even worse because 1) the groove in the rubber is not sufficiently deep, and 2) they've used a rubber mould with a metal casing; metal shreds plastic, especially unsanded edges like that of a cut-out in a metal chassis.


And I'm telling you the rubber where the "red square" is does not solve the problem sufficiently. Period.


The knot technique is really quite good -- assuming the underlying plastic casing is very, very strong/rigid, it works amazingly well, way better than rubber inserts. Some devices actually used a different kind of plastic where the cord ingress hole was (i.e. a stronger plastic), combined with the knot method, and that works wonderfully. I would trust something using the knot method with strong plastic over shitty rubber moulding with a 2mm groove in the rubber.

I fully agree that hot glue will not solve this problem. All that does is localise the stress point to where the hot glue begins; in those situations, cable pulling results in the actual wires literally ripping in half (which isn't ideal either). On the other hand, the knot method combined with hot glue (except applying hot glue at the ingress point where the controller cable comes in to the plastic mould itself) can actually work, but that's really not the point I'm trying to make. The point I'm trying to make is that the rubber used to "relieve stress" in controllers does not generally work well due to the issues I mentioned above; the knot method does work as long as you have strong plastic at the ingress point, and if you don't, the knot method + hot glue (at the ingress point) can work well.

koitsu , I agree on the same basics - that you are also agreeing - but you lose the point when trying to justify things too much:

OFCOURSE the mold in both cases is not made to hold up at a pulling contest.
OFCOURSE if you pull like a gorilla you will rip off the the 360 controller cable and the dvd one. That's common sense.

The point of this specific part of this mechanical contraption is absorb pulling shock as best as possible while holding th cable in place, and YES it is implied on the 360 controller that it made to protect the connector inside like in all devices, this is self explained.
In both cases 90% of the time under normal circumstances when you stumble on the cable the device will sustain and tension will most likely express by the 360 controller unplugging from the console and the dvd from the mains. Then there is the chance the device will develop a fault caused by hitting hard on surfaces like the floor.
But this is enough protection as those devices are home ones, not military grade ones. If you want to "solve the problem sufficiently" you do not use thin plastic/metal parts or simple cables.

But saying that the mold is not made to deal with pulling stress because if you use excess force you can brake it, is not a valid argument. It's like saying that your pants are not made to protect you from cold because if you go to Siberia you will freeze. Everything has it's limits.

I don't know about you guys but my pants won't freeze in siberia.

yes I can imagine what it's like

Thank you very much for the controller pinout! But does this support the four score adapter and zapper? Seems like you need to add atleast the (player 2) Joypad 2 D4 (pin 4) and D3 (pin 5) from expansion port. To make zapper work? Do i make the same connection for Joypad 1 (player 1) also? Or are the Joypad 1 D4 and D3 hidden somewhere on the board?

In the specific case of starting with an original plain Famicom motherboard: No, Joypad1 doesn't/can't have a D3 and D4. The part they used in the NES is used for something else in the Famicom.

To add D3 and D4 to joypad2, you'll need to jumper from the expansion port, as per http://famicomworld.com/workshop/tech/n ... v-famicom/

Thanks! That same diagram was the only thing i could find about the subject too.. But cause im making this with VGS Subor D21 (Famicom Clone), i was little confused about the Top loader motherboard..
I still need to figure out the Four score and Multitap difference problem. Seems like there is no easy, or best way to do it.
I think i try with both joypad wires and expancion port wires. And add switch for Four score or Multitap.
The Famicom Forum had some topic about the issue: http://www.famicomworld.com/forum/index ... pic=5912.0
So there is people who have done it. But i cant find clear instructions for this anywhere. I think i have to try make picture of the pinout for my self. To understand it better

The NES Four Score uses some kind of ASIC or PAL to emulate some combination of a 74'165, a 74'138, and a 74'153. The Famicom four-players adapter is an entirely passive device.

It uses an ASIC. I have one of these.