Wednesday, July 15, 2015

The Nintendo Family Computer/Famicom - The NES before there was a NES

Which one of these systems is playing the game?  Bonus if anyone notes the oddity regarding the game shown.
The Nintendo Family Computer, released in 1983, was the console which kick started console gaming in Japan and revitalized console gaming in the US as the Nintendo Entertainment System.  The Famicom had 1,056 licensed cartridge games released for it.  The system was directly supported for over eleven years with games.

The original console, of which Nintendo sold millions and millions, gets shortchanged these days.  People seek Famicom AV's for their detachable controllers, video quality and relative age.  People want top loaders because their cartridge slot is more reliable than a front loader.   Interest in front loaders is present due to the prices of the other systems and the easy obtainability of cartridge connectors.

Design decisions

The original hardware developers included items like the eject lever and the microphone, even though they were not strictly necessary.  A great deal of force is not required to remove cartridges from the slot.  The eject button made its way to the Super Famicom and the SNES, and it was equally unnecessary there as well.  The eject mechanism also makes it a bit cramped for modding purposes.

The microphone was intended as a novelty feature.  Using the microphone, you can hear a distorted version of your voice from your TV speakers.  However, it would later be used in games, mostly in a non-essential way.  Gaining the microphone meant losing the start and select buttons on controller II, so no Japanese game is likely to respond to Famicom AV's controller 2 start and select button input.  The Famicom AV was released in 1994 just as companies were no longer making games for the Famicom.  The holder of controller I has all the game select and game start/pause authority when playing games.

The color scheme of the Famicom, red and white, was intended to make the system look attractive to children.  Nintendo gave the controllers a touch of class with their metal face plates.  Those face plates did not hold up well over time against sweaty Japanese thumbs.  They have a tendency to show tarnish and wear unlike NES controllers.  The white plastic will become discolored by exposure to UV light.  Retrobright may be useful to restore the original color, but the stickers and decals may suffer from being submerged in oxyclean and peroxide.  My Famicom has been severely discolored from UV exposure, but the resulting color is something like a burnt orange and rather appealing.  The SNES is far worse.

Like the face plates, making the controllers hard wired and routing the cables through the rear of the console is another design decision straight from the 1970s.  Consoles released in the 1970s connected their controllers in the back and were frequently hard wired.  The idea was to reduce cable clutter and eliminate those "I can't find my controller" moments.  Because the controller cables were so short, instead of having the controller cables across the living room, the whole Famicom had to be pulled away from the TV, leaving the power and RF cables visible and frequently strewn across the room.  The NES introduced detachable controller ports located on the front of the console and every subsequent console since then has followed.

The controller cables were short because Japan is far more urbanized than the US.  Japanese gamers were accustomed to living, on average, in more confined circumstances than their US counterparts, so Nintendo believed they did not need to make long cables.  Even the Famicom AV controller cables are about half the length of the US version of the controller.  The NES revised controllers (dog bone) have a cable length of 93.25", and the regular NES controller has a length about 2" shorter.  The Famicom controllers have a cable length of just 29.25", and you loose 8.25" if you account for the width of the Famicom because the controllers come out of the back of the console.

The Famicom does not have a power LED, when you flip the power switch on, there is a little orange sticker that appears, showing you that the console is on.  Thankfully the power switch is not spring/latch operated like on the NES.  The reset button does not protrude above the enclosure, making it less likely that someone will press it accidentally than the NES's button.

The dust flap is unconnected to the eject mechanism and has no springs, so it has a cheap feeling.  It is just a piece of plastic that swings 180 degrees.  The NES's lid has a little tension in it, making it appear less cheap.  The Famicom Disk System RAM Adapter sits completely flush on the Famicom, whereas it has a slight overhang on the Famicom AV.  Even so, the Famicom is not that much larger than the Famicom AV.

The Famicom and the Famicom AV use the same power adapter, 10VDC, 850mA, center-tip negative.  Sega Master System and Sega Genesis Model 1 Power Adapters work perfectly and are easier to find in the US than Nintendo Famicom power adapters.

Inside the Famicom

Unlike every other iteration of Nintendo's 8-bit hardware, the Famicom's PCB is screwed into the top half of the shell, not the bottom half.  However, like the NES, the chip side of the PCBs face the ground.  All screws are Phillips head screws.

All Famicoms come with two PCBs, but the earlier Famicoms connect their PCBs solely by a ribbon cable. The smaller PCB houses the power conversion circuitry and the RF unit.  The larger PCB has the CPU, PPU and the rest of the chips needed to function.  The later VCI Famicoms have the smaller PCB sturdily connected to the larger PCB because the metal RF shielding on the smaller board is soldered to the larger board.  The larger PCB has the expansion port and a pair of headers for the controllers to plug into.

Hardware wise, there are roughly three generations of Famicoms.  First come the square button Famicoms.  These have rubbery square buttons on their controllers, smooth bottoms and are the least reliable of all the Famicoms.  Some may have survived the 1983 recall.  They also tend to have early and buggy revisions of the CPU and PPU.  They are pretty much museum pieces.

Next come the round button Famicoms.  They have solid CPU and PPU revisions and round plastic buttons on their controllers.  The bottom half of the case shell has a rough matted surface.  If treated properly, these will run well, but the video output is noisy and will show jailbars even without an AV mod once you know what to look for.

Sample video quality (does not capture the jailbars well)
Finally come the VCI Famicoms.  They have more robust RF shields, a metal shield fitted over the cartridge connector and more filtering capacitors.  They also have the power switch connected to the main PCB instead of the RF PCB as found on the non-VCI Famicoms.  VCI Famicoms can be distinguished from non-VCI Famicoms by the labels on the bottom of the case.

The Famicom has a comparatively minimalist design compared to the NES' PCB.  The NES PCB has an expansion slot which was never used, separately mounted power and reset buttons, separately mounted controller ports, a U-shaped cartridge connector, internal RF shielding for the top and bottom of the PCB, a tray-loading mechanism and extra circuitry for the lockout chip.

My Famicom works fine with the Everdrive N8 Famicom Edition.  The Everdrive is a bit of a tight fit inside the cartridge slot.  Square-button vintage Famicoms may have trouble with these devices. The NES PowerPak and NES game cartridges work with an adapter, I recommend this one :

Early CPU and PPU Revsisions

My Famicom is a round button non-VCI version, and it uses 2A03E and 2C02E chips, just like the first NES consoles. Its PCB is marked with HVC-CPU-07. The rev E CPU and PPU chips appear to be used in many of these non-VCI Famicoms, but I have seen revision A, B and D PPUs and revisionless CPUs.  The revision G chips appear to be the most common of all the CPU/PPU revisions Nintendo used in its products, but I have only seen them in VCI Famicoms.

Revisionless 2A03 CPU will be found mainly in square button Famicoms, but there are some later square button Famicoms with 2A03E CPUs.  The revisionless 2A03 lacks the short-period noise feature of the 2A03E and its successors.  Short period noise has a very metallic sound can be heard in Fire Man's stage in Mega Man 1 and Quick Man's stage in Mega Man 2.  Without short noise period the noise will sound like more typical white noise.  the It can also be heard at the end of the game over tune in Balloon Fight, but this may be unintentional.

The 2C02E and its predecessors lack the ability to read sprite data through a particular register.  Micro Machines uses this reading function to position graphics on the title screen and menu screens.  As a result, these graphics will look glitchy on a Famicom or a NES with a 2A03E or lower PPU revision.  This added ability was rather obscure and the timing was touchy.  There are no known instances of other games, licensed or unlicensed, using it in such a way as to cause noticeable visual differences as with Micro Machines.

The RF Output

The Famicom uses RF only-output, and it can be something of a pain to get working with US TVs.  The design of the RF unit is somewhat in between an Atari 2600 and a NES.  All three have the RF signal generating circuitry inside their respective consoles.  The Atari uses a TV/Game switchbox with a large sliding switch to select the game's signal or the antenna/cable signal.  The Famicom has the TV/Game switch integrated into the internal RF unit and has the physical switch on the rear of the console.  The NES has an automatic switch box where turning the console on acts as the TV/Game switch.

Options, options...
The Famicom did come with an external RF adapter.  This RF adapter is very, very odd by US standards because it requires you to strip cables to connect to the proper adapter.  Let me try to describe its operation.  The box has three screw terminals, one thin wire with the RCA plug and one thick wire with no plug.  The thin wire with the RCA cable, underneath the RF switch label in the photo above, goes to the Famicom.  That is the easy bit.  The thick wire is a 75 ohm coaxial cable which goes to the TV.  Some Japanese TVs will accept a bare cable, shown as #3.  In this situation, the ground wire mesh is held in place by a metal clamp and the thick signal wire is wrapped around one of the VHF terminals like a speaker wire.

If you do not have this kind of setup, something may have to go on the other end.  Owners could be expected to strip wire, something that would be intolerable today.  You can use a straight through F-type twist on connector, shown as #4.  Nintendo advised using a right-angle box that will fit the bare wire, shown as #1.  If your TV had only the 300-ohm split lead antennal terminals, then you would have to attach a 75-300 ohm converter, shown as #2.  Nintendo used to include ones in the Famicom's box where you could just snap the wire in.

Finally, the Famicom RF box required the same thing if you wanted to route an antenna or cable signal through it.  The two side-by-side terminals were for the 300-ohm split antenna leads.  The third screw terminal was to hold a 75 ohm cable in place and provide a connection for the ground mesh, and the signal wire wrapped around one of the two side-by-side screw terminals.  If your TV had 75 ohm inputs, all you had to do was to remove any connector from the cable wire and screw it as shown on the label.  Later Japanese Nintendo devices used the same RF switchboxes as the NES, making life a heck of a lot easier for many people.

The Famicom can use Japanese TV channels 1 and 2. Japanese Channel 1 uses the FM band in the 90-96MHz range, and channel 2 uses 96-102MHz.  In the US, the 87.9MHz-107.9MHz band was allocated for FM radio.  Later, cable channels 95 and 96 were allocated the frequencies used by Japanese channels 1 and 2.  In fact, the audio from the Famicom's RF unit can be heard in theory if you set your radio to 95.7 or 101.7 and touch the radio's antenna with an RCA cable from the Famicom's RF unit.

You can use Nintendo RF switchboxes with a Famicom.  However today it is easier just to use a thick RCA cable and a coaxial adapter, like an Atari 2600, unless for some reason you want to daisy-chain devices to the coaxial input on your TV.  I had little difficulty in setting my two CRTs to channel 95 or 96, but you may have to manually add those channels.  Keep your remote and TV manual handy.  I found that channel 95 was fuzzy on my TV while channel 96 was sharp, so I use channel 96.

US game consoles would often allow players to choose between channel 2, 54-60MHz, channel 3, 60-66MHz or channel 4, 66-72MHz.  A choice was almost always given because the user's area would often broadcast one channel more strongly than the other, giving for less interference with the weaker broadcast signal.  If your FM radio stations are particularly strong at the 95.7 and 101.7 frequencies, your picture quality may suffer.  However, where I live there is no strong 95.7 radio station but the 101.7 radio station is very clear.  This is counter-intuitive, but on Channel 1 (which overlaps the 95.7 signal) the video is fuzzy but on Channel 2 the video is much sharper.  There are more interference patterns on the Famicom RF than the NES RF, otherwise the video quality appears pretty close.


Leon Kiriliuk said...

I just wanted to thank you for this awesome blog! Keep up the awesome work. Super informative.

Anonymous said...

The yellowing is not caused by UV light, at least not that alone. An old console or computer that has been sealed in the box since it was new and never exposed to any light at all will still become yellowed. It is caused by the flame retardant Bromine yellowing the plastic over time. Retro-Brite will help a lot but only temporarily, the console will turn yellow again in a few years.

Sylvain Pypebros said...

nicely complements Nathan Altice's book "I AM ERROR" :)

Anonymous said...

Just got a non VCI Famicom with rev G chips, indeed quite uncommon but they do exist.