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Versions of the NES

Versions of the NES
by on (#112970)
A little question:
If we ignore region-specific NES versions and the top loader, are there different versions of the NES or are all versions the same?
With games, there are sometimes two revisions: PRG0 and PRG1. What about the console itself? If I bought a standard American NES console in 1985, is it identical to a standard American NES console that was sold in 1990? Is the NES from the first American release completely identical to the one from the Challenge Set (the box that contained "Super Mario Bros. 3")? Or are there differences?
Re: Versions of the NES
by on (#112971)
Don't know, but I bet you'd find some minor differences. Maybe they changed the layout slightly, or used different manufactures for the same components.
Re: Versions of the NES
by on (#112972)
O.k., layout is not that important (except for the gamepads). I would rather be interested in the technical differnces and if they could have any practical influence.
Re: Versions of the NES
by on (#112976)
I think there are different revisions of the CPU chip and maybe PPU chip. Also I believe they revised the hardware to try to prevent various lockout defeating methods. Something to stop hte CIC "stun" methods of running unlicensed carts.
Re: Versions of the NES
by on (#112979)
There are three known released versions of the CPU: 2A03 F,G ,and H. F is known to not have the "tonal" noise mode ($400e.7), but is believed almost entirely exclusively used in arcade machines. There almost certainly were revisions A-E, but I don't think we've seen them. I don't know how H differs from G; but it's conceivable it fixes DMA-triggered double reads.

There are five major variants of the NES, and they're visually different: the standard Famicom, the AV Famicom, 'toaster' NES, the NES2, and the AV NES. They have minor variations (Famicom read $4016 bits 3-4 are open bus; 'toaster' NES has the lockout chip).

Beyond that, there are multiple revisions of the mainboard for each. I don't know about anything but the 'toaster' NES, but it has 10 different PCB revisions. AFAIK, those differences are very minor, and mostly pertain to various lockout defeat mechanisms.
Re: Versions of the NES
by on (#112996)
Apart from the lockout stuff, have there ever been known things that actually influence the game once it is started?

Here some fictitious examples:

"If you change your weapon while being hit in Mega Man 6, Mega Man will have a wrong color. However, this only happens if you use an NES that was manufactured in 1985. The phenomenon does not occur with an NES from a later date."

"In the game Little Samson you will experience a slowdown at the third boss when you play with the NES from the Challenge Set. On all the other NESes, no slowdown occures there."

"The NES versions produced post-1989 have a little music stutter if too much is going on in Gradius which is not the case with earlier models."

Again, I'm not talking about differences between the actual different NES versions that were even marketed as different versions. I know that a Famicom is not identical to an NES. And a front loader NES is slightly different than a top loader NES. And a European NES is not the same as an American NES.
I'm talking about differences between machines that are generally supposed to be the same: Has there ever been a case where a standard American front loader NES behaves differently than another standard American front loader NES because they were manufactured at different times and thus use slightly different hardware? (Not counting the lockout chip mechanism and the mere tolerance of accepting or declining unlicensed games.)

On PCs, it can make a difference for example what graphic card I use. Has something similar been observed with the NES too? Like that the machines that were produced between April and September 1987 have a certain chip by Sharp while other versions have the chip by Fujitsu. And the models with the Sharp chip have some tearing problems with parallax scrolling, even though the NES was not advertised as a new version and is still supposed to be the standard NES.
Has something like that or something similar ever been observed? Or does every front loader US NES behave exactly the same?
Re: Versions of the NES
by on (#112998)
JimDaBim wrote:
Apart from the lockout stuff, have there ever been known things that actually influence the game once it is started?

Here some fictitious examples:

"If you change your weapon while being hit in Mega Man 6, Mega Man will have a wrong color. However, this only happens if you use an NES that was manufactured in 1985. The phenomenon does not occur with an NES from a later date."

"In the game Little Samson you will experience a slowdown at the third boss when you play with the NES from the Challenge Set. On all the other NESes, no slowdown occures there."

"The NES versions produced post-1989 have a little music stutter if too much is going on in Gradius which is not the case with earlier models."

Again, I'm not talking about differences between the actual different NES versions that were even marketed as different versions. I know that a Famicom is not identical to an NES. And a front loader NES is slightly different than a top loader NES. And a European NES is not the same as an American NES.
I'm talking about differences between machines that are generally supposed to be the same: Has there ever been a case where a standard American front loader NES behaves differently than another standard American front loader NES because they were manufactured at different times and thus use slightly different hardware? (Not counting the lockout chip mechanism and the mere tolerance of accepting or declining unlicensed games.)

On PCs, it can make a difference for example what graphic card I use. Has something similar been observed with the NES too? Like that the machines that were produced between April and September 1987 have a certain chip by Sharp while other versions have the chip by Fujitsu. And the models with the Sharp chip have some tearing problems with parallax scrolling, even though the NES was not advertised as a new version and is still supposed to be the standard NES.
Has something like that or something similar ever been observed? Or does every front loader US NES behave exactly the same?


I believe no such difference has been documented. The only one may be the earliest no-periodic noise 2A03 (which I think never reached the NES itself) and apparently some early CPU / PPU bugs in the first run of Famicoms (the square button ones).
Re: Versions of the NES
by on (#113003)
Alright, then everything is fine.

Didn't they have to recall the Famicom when it was already out because of such a bug?
Re: Versions of the NES
by on (#113006)
Yes the Famicom was recalled and re-released later. I'm not sure what the apparent problems might have been. There are some original Famicoms in the hands of collectors.
Re: Versions of the NES
by on (#113007)
Quote:
"If you change your weapon while being hit in Mega Man 6, Mega Man will have a wrong color. However, this only happens if you use an NES that was manufactured in 1985. The phenomenon does not occur with an NES from a later date."

"In the game Little Samson you will experience a slowdown at the third boss when you play with the NES from the Challenge Set. On all the other NESes, no slowdown occures there."

"The NES versions produced post-1989 have a little music stutter if too much is going on in Gradius which is not the case with earlier models."

My bet is that those are fake, or at least involuntary made up by wrong assumptions. I can't see how a different PCB layout or different lockout defeat, or even a different CPU revision, could have those effects.

I think the CPU revision can affect controller reading, and OAM reading though.
Re: Versions of the NES
by on (#113009)
A CPU-controlled CIC stunner, such as that seen in Color Dreams games, might need different numbers of resets on different NES revisions, and that might change certain things that depend on CPU/PPU alignment.
Re: Versions of the NES
by on (#113013)
There is also an RP2A03 that has no revision letter, I have one on a VS Unisystem PCB. I don't know what's different about it. Some have reported though that an H-revision CPU doesn't work with a few VS games (TKO Boxing was one that comes to mind, if anyone was curious).

I know the first post said no region differences, but one of those that's interesting is that the controllers from the NTSC NES don't work on a PAL NES. IIRC, was something to do with a resistor change on the controller board.
Re: Versions of the NES
by on (#113015)
JimDaBim wrote:
Alright, then everything is fine.

Didn't they have to recall the Famicom when it was already out because of such a bug?

Yeah there are a lot of differet Famicom board revisions and the earlier square button ones have a problem where they freeze when playing sometimes, but nobody really seem to know the details. Revision HVC-CPU-05 is the last of the square button versions and the only one of them that doesn't have the freezing problem I think. There are round button 05 units as well but some of them might just have had their controllers changed, because the square buttons often broke. The HVC-CPU-XX run has at least 8 revisions.
Then there is the later HVC-GPM-XX run with at least 2 revisons and HVC-GPM-02 being the most common one.

GPM-02 is reported to have a fuse which earlier models don't have and the sound may be a bit different between revisions. It's hardly noticable between the red and white Famicoms though. This video (under ロットロット) http://retrogame-db.com/%E3%83%95%E3%82 ... %E3%83%88/ shows a comparison between many revisions including New Famicom and the Twin Famicom variations.
Other than that I don't know if there's any notacible differences between board revisions when playing games.

Proof of a CPU-08 revision (rare):
http://offgao.blog112.fc2.com/blog-entry-22.html

Proof of a CPU-01 revision (first version I guess, probably extremly rare):
http://offgao.blog112.fc2.com/blog-entry-24.html
The 01 verison seems to play some games without trouble but both Rambo and Fantasy Zone has graphic glitches with this particular unit.
Re: Versions of the NES
by on (#113016)
Bregalad wrote:
My bet is that those are fake, or at least involuntary made up by wrong assumptions.

Erm, yes they are:
JimDaBim wrote:
Here some fictitious examples:

I consciously made up some hypothetical situations to demonstrate what I mean with "different behavior" to ask if something in this category was ever observed. You know, like different graphic cards on PCs can affect the smoothness of scrolling in a game.

Bregalad wrote:
I think the CPU revision can affect controller reading, and OAM reading though.

How would this express itself? What could be different?
Re: Versions of the NES
by on (#113019)
JimDaBim wrote:
Bregalad wrote:
I think the CPU revision can affect controller reading, and OAM reading though.

How would this express itself? What could be different?


I think most games that would be subject to this bug were aware of it so they required the same value for more than one read. Because of this the end user wouldn't notice whether the bug existed or not.

To answer your question: No. There aren't any noticable differences in the different versions of the NES to the end user aside from the CIC circuitry. Meaning that some early pirated games might only work in old NES's. But if the game runs you'll never see any differences. Sure Nintendo could have fixed/improved some minor things but you'll never notice them even if they exist unless you're a dev'r specifically looking for these extremely obscure differences to the end user...

There are no differences on the level of what you're asking 'scrolling is different for different graphics cards' I'd bet large sums you won't find anything like that. If there were, we would have noticed it by now...

As an aside why are you curious? Is there something specific you're wondering about?
Re: Versions of the NES
by on (#113030)
No, it's nothing specific. I was just asking myself: Since there are some revisions of games (PRG0, PRG1), you might want to get a specific version because in it a certain bug from a previous version is fixed etc. And I wanted to know if the same is true for the NES console itself: That certain revisions of the console might be better than others because some consoles might treat certain games incorrectly or something like that.
That was my only motivation for asking it. I just wanted to know if something like that exists and if the consoles might differ in the same way two revisions of a game might differ.
Re: Versions of the NES
by on (#113031)
I'm sure Nintendo would have had no problem doing cost-reducing slight redesigns.
Re: Versions of the NES
by on (#113472)
I have a very old toaster NES (smooth plastic on the bottom, very low serial number) which has noticeably darker video output than all of my later models, close to that of my AV Famicom. I used to prefer using it over my other toasters because the picture looked so much cleaner (sharper edges and less fringing) on my CRT.

My PowerPak has also exhibited different glitches on different consoles; on my AV Famicom, it shows a duplicate cursor in the main menu that jumps around erratically. This may be due to the 72-to-60-pin converter I'm using adding resistance or otherwise changing the characteristics of the data lines, though (I have a bootleg Takahashi Meijin no Bouken Jima 3 cart that has similar issues in a toaster when using a converter).
Re: Versions of the NES
by on (#113501)
Mine shows a dupe cusor but only for awhile after power up. If you move it around a bit it eventually goes away and there is only one cursor. I have no idea of the date on my NES console.
Re: Versions of the NES
by on (#113503)
Another case of manual $2004 writes not working properly.
Re: Versions of the NES
by on (#113504)
thefox wrote:
Another case of manual $2004 writes not working properly.

So we have evidence of this? Last time I mentioned having heard that manual $2004 writes were not reliable everyone looked at me like I was crazy!
Re: Versions of the NES
by on (#113505)
I think I had some notes of mine that manual $2004 reads/writes only work reliably on a certain CPU-PPU alignment.
Re: Versions of the NES
by on (#113507)
I asked about this a couple months ago. viewtopic.php?f=9&t=9912
Quietust had a few ideas as to what might be breaking (more OAMADDR oddness). There were a few confirmations, too.

Regarding alignment, at least for me, it seems to be more often a thermal issue. But "alignment" plus "thermal" would be code for "timing", since ICs get slower as they get hotter.
Re: Versions of the NES
by on (#113516)
Alignment is, as far as we know, the only difference between a manual write to $2004 and use of $4014. So that might be the only reason manual writes doesn't always work.
Re: Versions of the NES
by on (#113555)
Wouldn't it be the same as far as the PPU is concerned? Manual $2004 and $4014 writes involve the 2A03 doing $2004 writes to the PPU with the same timing.
Re: Versions of the NES
by on (#113556)
blargg wrote:
Manual $2004 and $4014 writes involve the 2A03 doing $2004 writes to the PPU with the same timing.

Are you sure it's the same timing, even down to the half master clock? With manual $2004 writes, the 6502 is doing the writes. With $4014 writes, the DMA unit is freezing the 6502 and doing the writes itself. Besides, in a DMA, the cycle prior to the write was a read of the correct value, leaving the correct value on the data bus, while in a 6502-mediated write, the previous value on the data bus was more than likely $20 for the high byte of the destination address.
Re: Versions of the NES
by on (#113565)
I am pretty certain that there is no mechanism for the M2 duty cycle to be anything other than 5/8 on the 2A03.
Re: Versions of the NES
by on (#113576)
But that still leaves 1. when the address lines become valid, which affects the chip select going into the PPU, and 2. what value is held by bus capacitance before the write cycle begins. Perhaps in the STA $2004 case, the CPU isn't meeting the PPU's setup and hold requirement on some alignments.
Re: Versions of the NES
by on (#113583)
Then you should see if doing any writes to $2004 make sprites use tile $20 at position ($20, $20) behind the background. If so, then it's possible that the PPU somewhat latches the data lines one cycle before the actual write and use this value ?
Re: Versions of the NES
by on (#113592)
... You know, I tentatively think I saw that as one of the failure modes in my "just how cranky" thread.
Re: Versions of the NES
by on (#113597)
JimDaBim wrote:
Apart from the lockout stuff, have there ever been known things that actually influence the game once it is started?

Here some fictitious examples:

"If you change your weapon while being hit in Mega Man 6, Mega Man will have a wrong color. However, this only happens if you use an NES that was manufactured in 1985. The phenomenon does not occur with an NES from a later date."

"In the game Little Samson you will experience a slowdown at the third boss when you play with the NES from the Challenge Set. On all the other NESes, no slowdown occures there."

"The NES versions produced post-1989 have a little music stutter if too much is going on in Gradius which is not the case with earlier models."

Again, I'm not talking about differences between the actual different NES versions that were even marketed as different versions. I know that a Famicom is not identical to an NES. And a front loader NES is slightly different than a top loader NES. And a European NES is not the same as an American NES.
I'm talking about differences between machines that are generally supposed to be the same: Has there ever been a case where a standard American front loader NES behaves differently than another standard American front loader NES because they were manufactured at different times and thus use slightly different hardware? (Not counting the lockout chip mechanism and the mere tolerance of accepting or declining unlicensed games.)

On PCs, it can make a difference for example what graphic card I use. Has something similar been observed with the NES too? Like that the machines that were produced between April and September 1987 have a certain chip by Sharp while other versions have the chip by Fujitsu. And the models with the Sharp chip have some tearing problems with parallax scrolling, even though the NES was not advertised as a new version and is still supposed to be the standard NES.
Has something like that or something similar ever been observed? Or does every front loader US NES behave exactly the same?


I have a copy of Super Mario World for the SNES that doesn't slowdown with 3 fishes and a Yoshi.
Re: Versions of the NES
by on (#113605)
psycopathicteen wrote:
JimDaBim wrote:
Apart from the lockout stuff, have there ever been known things that actually influence the game once it is started?

Here some fictitious examples:

"If you change your weapon while being hit in Mega Man 6, Mega Man will have a wrong color. However, this only happens if you use an NES that was manufactured in 1985. The phenomenon does not occur with an NES from a later date."

"In the game Little Samson you will experience a slowdown at the third boss when you play with the NES from the Challenge Set. On all the other NESes, no slowdown occures there."

"The NES versions produced post-1989 have a little music stutter if too much is going on in Gradius which is not the case with earlier models."

Again, I'm not talking about differences between the actual different NES versions that were even marketed as different versions. I know that a Famicom is not identical to an NES. And a front loader NES is slightly different than a top loader NES. And a European NES is not the same as an American NES.
I'm talking about differences between machines that are generally supposed to be the same: Has there ever been a case where a standard American front loader NES behaves differently than another standard American front loader NES because they were manufactured at different times and thus use slightly different hardware? (Not counting the lockout chip mechanism and the mere tolerance of accepting or declining unlicensed games.)

On PCs, it can make a difference for example what graphic card I use. Has something similar been observed with the NES too? Like that the machines that were produced between April and September 1987 have a certain chip by Sharp while other versions have the chip by Fujitsu. And the models with the Sharp chip have some tearing problems with parallax scrolling, even though the NES was not advertised as a new version and is still supposed to be the standard NES.
Has something like that or something similar ever been observed? Or does every front loader US NES behave exactly the same?


I have a copy of Super Mario World for the SNES that doesn't slowdown with 3 fishes and a Yoshi.


I'm not sure what you are referring to, but I am 99.99% sure that this difference is in your head...
Re: Versions of the NES
by on (#113611)
If you do have a copy of Super Mario World that doesn't slow down in areas where other copies do, you need to loan it to a speed runner :D
Re: Versions of the NES
by on (#113613)
It's a SMAA+SMW cart that came with the system I bought back in 1996 at a Toys "R" Us in the Chicago area. I've played all 96 levels and there isn't a single level that lags with 3 fishes and a Yoshi.

I don't even know which underwater level it supposed to be anyway.
Re: Versions of the NES
by on (#113624)
I know they changed SMW for the SMAS 5-in-1 to make Luigi not a palette swap, and the save code surely coexists with that of SMAS. Perhaps they optimized some of the SMW code while they were at it. It'd be plausible because code in launch titles tends to be total crap because they were developed before the programmers learned basic optimizations, and often before the system's hardware was even settled. Or does the old one run on slow ROM and the new one on fast ROM?
Re: Versions of the NES
by on (#113627)
SMA + World says SlowROM in the imbedded cartridge information. So if the original slows down and the SMA+W does not, they must have changed something about how the game runs. This could be expected since the cartridge doesn't employ bankswitching hardware to combine World with SMA.
Re: Versions of the NES
by on (#113629)
Where are you getting this "3 fishes and a Yoshi" slowdown figure from? When was the last time you compared the SMAS+W cart to an original SMW cart?

I'm not aware of any major code changes that were made to the game, other than the addition of alternate Luigi sprites (which aren't even stored in the game's standard graphics compression format) and the gutting of the original save file menu. If there were any, surely SMW Central would have found and documented them by now.
Re: Versions of the NES
by on (#113669)
BMF54123 wrote:
Where are you getting this "3 fishes and a Yoshi" slowdown figure from? When was the last time you compared the SMAS+W cart to an original SMW cart?


The people at Sega-16 claimed that there is a level in SMW that lags with "3 fishes and a Yoshi." They never said what level it was.
Re: Versions of the NES
by on (#113688)
So no direct comparison has actually been done, then... :?

I'm going to assume Sega-16 was playing the game in ZSNES or something, which did introduce extra lag in my old SMW hack that's not present (or greatly reduced) on a real console. I'm quite certain it takes more than three enemies and a Yoshi to bring the original game to its knees.