Anatomy of a cheap USB-to-Ethernet adapter
projectgus.com
projectgus.com
Note that if you do choose to buy the cheaper one without any shielding, it's your responsibility (in the US) to prevent it from interfering with licensed users of the RF spectrum. (In this case, 25m shortwave broadcasters on 12MHz and government-run time-transfer services, like WWV and WWVH, on 25MHz.)
If your device is particularly annoying to some shortwave listener, expect to get a letter from the FCC telling you to shut the thing off.
(I looked up a few of the letters, and I really appreciate the politeness from the government: http://www.arrl.org/files/file/Part%2015%20Letters/04-06-24-... "There are several simple and inexpensive steps that can be taken to eliminate interference from battery chargers, and we would be glad to send them to you if needed.")
"You apparently discarded the toroid devices, tossing them in Mr. (deleted) yard. The devices were simple and non-intrusive, and we can envision no reason whatsoever for you not to continue using them, other than a desire to be uncooperative."
Dabbling in RTL-SDR for a bit quickly brought me up against the interference monster, and since the USB sticks are typically powered by bus if no direct power modifications are done one of those sources of interference was hooked right into the receiver. Toroid cores either clipped on or looped were indeed the answer for quieting the cable. This doesn't help much if the interfering device is emitting really badly off the board itself though so manufactures shielding their devices as a standard is rather welcome.
http://www.arrl.org/files/file/Part%2015%20Letters/04-09-29-...
And an Apple adapter: http://www.righto.com/2012/05/apple-iphone-charger-teardown-...
The Apple device is UL listed, so they can't cut the same corners the Chinese manufacturer can. The same is true of any UL listed USB power adapter.
It bugs me that Apple customers seem to get ripped off by their brand for simple things & then they thank them for it. I'm glad a 3rd party market for Apple stuff finally emerged. I remember the dark ages when you couldn't even tell your friend "check ebay I'm sure theres one of those..."
Part of the reason I am still in the PC world vs Mac (I build my own powerhouse desktops for research data-mining & gaming, buy cheap laptops for practical use) is that the multitude of companies making parts means they find the proper price/quality balance much more often.
I'm glad this author gives credit to the off-brand. I'm very impressed with the quality of cheap Chinese electronics, and if it breaks you have 8 or so more tries to get it right before you reach the same amount spent. & plus, let's face it the main problem with this stuff is that you lose it, not that it breaks so I have a tendency to sway way toward the cheaper end with non-essential cabling & components for that reason.
Inside my research PCs is a different story... no expense spared on CPU/GPU/drives/mobo/etc. :D
> The Windows drivers are the exact same digitally signed ones that Microsoft distributes through Windows Update
AFAIK there is a standard device class for "USB ethernet controllers", so any chipset that conforms to it will work fine with the standard drivers.
As for the unmarked chip - many IC companies are not averse to creating custom designs for a specific customer (and marking it however you want) if you're willing to buy enough. I don't think it's ASIX since they don't have the single 25MHz clock source; more willing to bet on Microchip or SMSC.
Note that it identifies itself to the system as ASIX, though. Of course, it could be that other companies actually have a license to make ASIX things...
You're spot on about the PLL stage, a few people on Reddit pointed the same thing out when I first posted it. Makes sense, although I still think it's interesting they added it internally to an otherwise (apparently) cloned design.
You're also right that USB CDC does provide the option for a generic USB Ethernet device, however this silicon is ASIX-specific (not just the USB IDs.) ASIX's Windows drivers include their own system driver binaries, and the ASIX Linux driver has a lot of ASIX-specific stuff in it.
I think it's kind of possible ASIX made this themselves as some kind of no-name branded unadvertised market segmentation effort. I can't understand what their rationale would be exactly but hardware companies do unusual things sometimes...
IC companies make unadvertised products all the time, for anyone who is willing to buy enough... look at Apple's Lightning cable and TI's BQ2025, for instance.
It has an ASIX AX88179 which is a USB 3.0 to Gigabit chip and it my tests I was easily able to get around 800-900Mbps. It also has 3x USB 3.0 ports, so not only do you not lose your USB 3.0 port you gain 2 more. I've not dismantled it but it feels solidly built.
Here in the UK I paid the same price as the Apple USB to Ethernet Adapter, which is only 100BASE-T and offers no hub.
http://www.amazon.com/gp/product/B00EHDNAOE/ref=as_li_ss_tl?...
(I have an unbranded Android phone that assigns a random MAC address every time I turn WiFi on/off. Apparently this happens since they didn't bother to initialise the EEPROM and just left it at all zeroes. But this means being harder to track, so I consider it more a feature than a bug...)
The scope test might be do-able on a comparison basis between the two designs. It's possible that Apple over-engineered their shielding.
It's not necessarily a cloned design. The cheap part may simply implement standard protocols, and use the name of the Apple part to ensure driver compatibility without too much testing. Still, that seems rather under-handed if it's what it seems.
Isn't it pretty well known that 1) they aren't secretive and 2) they don't actually design their own hardware. They start off by producing the legitimate item, in the factory that's contracted by the company who designed the product. If the product is successful or easily fits in their existing knockoff fabs, they plans are basically copied over
Author does not decap the chip, but the implication is that there was indeed some real engineering that went into the design of the clone.
It _is_ possible, of course, that the original has excessive margins and the counterfeit one is a tighter design. We'd have to see the eye diagrams on both sides to be sure.
I would've liked to see the OP do a benchmark on transfer rates between the original and the clone. (Unless he aleady did one and didn't find any difference.)
"When I ran a TCP throughput test with iperf, they both performed well. The Apple adapter measured throughput of 94.3Mbps. The cheap adapter measured 87.4Mbps. By comparison, the builtin ethernet on my laptop measured 94.8Mbps (after being set from gigabit to 100Mbps.)"
So, there is a difference, but it's relatively small (and possibly acceptable for the things people use ultra-cheap ethernet adaptors for).
The throughput drop could be due to packet loss, maybe from more noisy circuitry, or it could be due to a bottleneck on the USB side of things. Smaller packets are good at finding those because they generate more events per unit time.
I saw this with a bunch of crappy WiFi dongles. The radio can run at the 54Mbps or whatever but the USB interface tops out at 20.
I'd venture the shanzhai chinese geeks fiddling relentlessly with hardware in Guangzhou are much closer to Steve Jobs' ideal than the average Apple Store clients.
On one side you have rich kids who can afford a $30 dongle, knowing perfectly (after reading this article) that they are giving away $25 to a marketing department and that they are bowing to their own voodooish cargo cult. These guys are simply afraid of the remote possibility of having to spend 5 mn of their precious time checking a connection, and maybe too, something really catastrophic! lose ONE of their 10.000 instagram pizza photos because of a subpar component in their setup.
On the other side you have these ugly hackers who are photocopying hardware components for 1 year old companies named Yunxingdianziguangzhoujituanyouxiangongsi, and their logo is ugly, and these guys are Chinese! I know them: they are hungry, not only hungry for money, but also hungry for knowledge, recognition, they are curious about the world, about the future, and they have no fear for bad taste: a pink iPhone clone with teddy bear shape? check!
Also I don't know why you would refer to the guys as "ugly" and why you exclaim that "and these guys are Chinese!" There's something subtly racial about your view in the whole post. Would it be any less of an exclamation if they were Peruvian?
- For me being "foolish", in the mouth of Steve Jobs, means not caring at all about what other people will say or think. I see a link with the peculiar "bad taste" of shanzhai: they do not care what "good taste" people think of pink Teddy bear shaped phones.
- I am living in China since 10 years, my wife is Chinese, my kids are half-Chinese, all my colleagues and many of my friends are Chinese. My comment was not "subtly racial", it was (trying to be) ironically emphasising the fact that in some people's disdain of shanzhai cheap gadgets, there is also the fact that those who build them are Chinese.
Just like 30 years ago saying a car was Japanese meant something cheap, copied, second-grade, right now the same applies to Chinese manufacturing.
And, in fact, often justifiably so! There are three kind of products quality made in China:
1) The very cheap that is sold in developping countries (have you ever seen those electric plugs with a single hair of copper inside for conductivity? cost nothing, burns after 10mn use).
2) The high quality sold to developed countries with Western brands. E.g. the Apple usb dongle in question here.
3) The medium quality sold internally and in developed countries as cheap alternatives to 2) above.
By the way, this 3) class is the most interesting because as the Chinese middle class raise its income level, it will have to become better and better, until a Chinese brand will do better than what is imitated currently (just as Japan did with cars, hifi, etc.).
I hear often that Chinese people cannot produce quality because of some of their "cultural atavism", and I think this is very wrong. In the past, they were manufacturing the best of breed in many domains, and in all their region of influence having "北京" (Beijing) stamped on goods was enough to triple its price.
Some people will buy Apple just because it's Apple and they want "original" stuff; others will buy Apple because they read these articles and know that the parts are high quality; others will buy the cheapest one they can find among amazon, ebay, monoprice and korean websites (probably laughing at those who buy Apple parts).
I don't think there's an easy market for "non-Apple and midprice".
(They also sell a USB3-gigE adpater for $25)
The cheapest Asix 88772-based one I can find from a reliable seller is 25RMB including shipping.
It seems like there is another 50 cents that can be cut from the design, although the RD9700 may not have an OSX driver: http://forums.macrumors.com/showthread.php?t=1450026
It also comes in a 32-pin package, and comes from a shady-looking company (http://www.corechip-sz.com/ ) that has parts numbered 6872 and 6873, so the "RD6877" on the PCB of OP's clone suggests it might be a RD6877.
Does that mean the RD9700 devices on taobao (22RMB) are likely to work on OSX without additional drivers, as they pretend to be an Asix chipset?
The speeds OP got are higher than 12Mbps, so I guess it's not an RD9700 in disguise.
Just guessing. I'm about to order the 25RMB asix-type one.
It seems to work fine on a Mac, though.
Most of the time, the cheap no-name electronics I've encountered have been pretty feature-complete, or even feature-laden, and any bugs were usually minor annoyances rather than fatal flaws.
But the quality control is a crapshoot, so a good chunk of them tend to be DOA. Of the ones that work fine at the start, many will fail in the following weeks, months, and years at much higher rates than you'd expect.
So I guess the question is, is the one with the fruit on it worth $25 more? It seems like the cheap one is more "Wozniak" in approach.
The guts of it (the electrical bits) looked fine, worked properly, etc. It was the mechanical design that gave me problems. Replaced it with a (ridiculously expensive at $29.99) higher end version and that has lasted me quite some time.
(And even less reason for it to cost $29, but that seems to be Apple's default minimum price for an accessory.)