8 ms·

I partly agree that it's a bit harder than before. But a lot of the faulty devices we're seeing are just straight up using an incorrect resistor value or simila

by dmoy 9y ago

I partly agree that it's a bit harder than before. But a lot of the faulty devices we're seeing are just straight up using an incorrect resistor value or similar, and apparently released to the public without proper testing. Maybe that's on USB spec people for not having good material, but on the other hand maybe that's on the manufacturers for not hiring EEs who can actually read a damn spec sheet properly...

fjsolwmv 9y ago
It's cost cutting to make cheaper cables and ports.
- lvh 9y ago
  Or intentional trivial incompatibility to sell _more expensive_ cables and ports :)
  - gregmac 9y ago
    That's a scary possibility. Flood the market with barely-functional garbage in the low range so that consumers can't figure out which cheap ones are actually usable and just pay more to avoid the headache. It's not dissimilar to the box store HDMI/audio/etc cable strategy: Cheap, absolutely garbage cables at a mid-range price, or upper-mid-range cables at grossly over-inflated prices. Consumers tricked because of course the $200 HDMI cable looks noticeable better than the $20 one. Reality is the real retail prices of cables they're comparing should be more like $2 and $20, and the difference between that $20 cable and one that actually would cost $200 is only noticeable with high-end test equipment (or by 'audiophiles', who have the super-power of being able to see/hear a difference in cables as long as they know the price).
deleted 9y ago
[deleted]
- deleted 9y ago
  [deleted]
heisenbergs 9y ago
This was the case when the original USB came out first too. It took a good couple of years to mature. I think these are normal standardization issues...
- Someone1234 9y ago
  Difference is that when the original USB spec came out it wasn't delivering enough power to kill somebody, contrast that with today where a USB-C error could be fatal. See: https://www.theverge.com/2016/2/4/10916264/usb-c-russian-roulette-power-cords https://www.theverge.com/2016/2/4/10916264/usb-c-russian-rou...
  - MisterTea 9y ago
    This is incorrect. The high power charge is 20 volts, below the safe threshold of ~50V set by such agencies as: OSHA, NFPA, ANSI, IEEE, UL, IEC and others. The real difference is USB was a completely new technology with zero market penetration so growing pains were inevitable. USB-C should not have these growing pains as they should have learned from 20+ years of developing the standard.
    - gok 9y ago
      There is relatively little risk of electrocution but 100 watts can still be more dangerous than 10 watts. Overheating and fire are a much bigger risk.
    - derefr 9y ago
      Is it really large, established manufacturers who are making these mistakes? Or is it random fist-time hardware entrepreneurs in Shenzhen? Analogy: we don’t blame Javascript-the-language-standard for the Node community’s constant (and usually half-assed) reinvention of build tools. Javascript itself didn’t cause that. More than likely, it was a glut of newbie developers joining the community—and building tools for one-another, rather than leaving it to the experienced people—that caused that.
      - 9y ago
Cthulhu_ 9y ago
Is it just a resistor, or is it one of hundreds of possible resistor depending on factor X? USB or any connection should be simple - you know, like code. The more exceptions and options you add, the harder it becomes to properly implement it. This is exponential, too, not linear.
TheSoftwareGuy 9y ago
>EEs who can actually read a damn spec sheet properly... I think this is the hardware equivalent of expecting programmers to write bug free code on the first try. Most of the time when a programmer wants to implement something a little complex and a little outside their expertise, they use an external library. Likewise, EEs will often buy a chip produced by a third party manufacturer and use that to handle it. But the abstractions available to EEs are often a bit more leaky than those available to us programmers, since they are more constrained by the laws of physics. and as a result that third party chip is still harder to use than a software library.
- throwahey 9y ago
  That is still an avoidable error. You shouldn't be adding parts without understanding how they work or how they will affect your circuit as a whole.
- baddox 9y ago
  On the first try? I would hope that hardware manufacturers don't take the engineers' first attempt and immediately go into mass production.
- ChuckMcM 9y ago
  That isn't the way EE's are trained in my experience. When new hardware is designed that is outside the EE's experience there is usually an evaluation board available from the manufacturer. They get one of those in house, read the application notes and data sheets, and use their test equipment to observe the 'proper' signal levels and waveforms on a correctly implemented system. Then they add this part to their design, and lay out the schematic and the printed circuit board according to best practices by the manufacturer. Once the first boards return they put measure the signal levels and waveforms in their circuit to verify they are with the specifications and that they match the ones on the eval board. Then they will 'corner' test the circuit (corners are low/hi temperature range, low and high voltage range) and verify it continues to work according to specification at all the 'corners' (if it does then you are generally ok with assuming it will work at all points "inside" those for corners.) There are people who are either in a hurry or don't care who wire something up according to the application note, power it up once and call it 'good'. I've seen a number of cost reduced 'clone' equivalents that meet that description. @kens has done a number of blog posts that show this sort of mentality in detail.
logicallee 9y ago
It must be more than "engineers can't read a spec" because decices using previous versions of USB tend to be fine. So why can engineers read those specs? (Why didn't they "choose an incorrect resistor value" for previous generations of USB, then?) This spec by contrast must be far more complicated[1]; also since it is so much faster, can't quality components supporting it all be more expensive - leading to cutting corners as a cost cutting feature? Also if as a consumer you can't predict what "should" be about to happen (which way power will flow, what will be host) that is down to a bad spec re connector types. For example couldn't a universal visual indicator on a port (including the bottom of a phone) indicate its capabilities and what will happen very clearly? (Through symbols.) They do not. Couldn't a software popup make you choose? They do not. Not to mention that it is not clear what should happen. If a phone can power a USB peripheral (like usb on the go) that means it could charge a second phone. So if you connect two phones which one should charge the other? With old versions of USB phones the answer is simple: whichever one you put an on the go converter into, making it a master instead of a phone's usual role as a slave. The fact that the spec does not make these as clear for USB C is down to the spec and design. Can't USV C simply be badly designed? (overdesigned, underdesigned, badly designed.) [1] Consider that a 1-page spec that can be read and implemented quickly in 15 minutes, can be implemented by anyone. A five-thousand page spec that takes 1,000 hours to read and understand can be implemented by no one (only teams). In between we have both previous versions of USB and USB C - but is it possible that USB C is too far in the latter direction?
- daurnimator 9y ago
  > Couldn't a software popup make you choose? They do not. They do when I e.g. connect two android phones together.
  - logicallee 9y ago
    Got it (never tried it).
amluto 9y ago
A sane USB-C spec would not have required a resistor for an A-to-C cable.
- kjdndisneinj 9y ago
  A single resistor is seriously not challenging to get right. If they can't do that they sure as hell shouldn't be making a cable.
  - amluto 9y ago
    Your average cable is some wire, some connectors, and plastic. Adding a resistor adds a whole extra element to the process, which is a big deal for a part that sells for probably well under $1 wholesale. Cable shops probably have no experience with circuits. The USB-C spec for some reason made it so that cables with no resistor or with the wrong resistor still seem to work but are unsafe. Of course the result is a mess.
    - tadfisher 9y ago
      Just about every video game console made between the late 1980s and mid-2000s had an official video-out cable with one or more resistors [1]. It's not an unheard-of thing. [1]: http://members.optusnet.com.au/eviltim/gamescart/gamescart.htm http://members.optusnet.com.au/eviltim/gamescart/gamescart.h...
ljm 9y ago
Is it really that simple? Just changing a resistor value? I got an XPS 13 for work, it’s all USB-C, and the versatility of the port is fantastic (doesn’t matter which port I plug into, it still charges, so I don’t have to wrap the power cable around the back of the machine or sit in a weird position to keep some slack in the wire). However, I took it to the office and naturally I plugged my power adapter into one port. I then plugged in the monitor (also USB-C, delivering power), and the two ports cancelled themselves out and confused the OS. Windows thought I was charging the laptop yet it also said the battery was depleting. They were negating each other and the battery loss continued as it would with no power connected. It makes sense for a monitor to power the laptop because it’s mains connected. But then you have one of those classic programming problems: if there are multiple inputs providing the same thing which do you consider the source of truth?
- criddell 9y ago
  They could always ask the user if they are that confused then remember the answer so they don't have to ask again.
  - ljm 9y ago
    Can you imagine a typical laptop user who assumes everything 'just works' (like me, by virtue of thinking I need to power my laptop while attaching a powered monitor) seeing a prompt in the OS about which thing should provide power and which should either reject it or use it to charge a battery?
    - acct1771 9y ago
      Can you imagine someone not understanding a clearly worded UI that they use to do the things they have to do to function in society?
- dmoy 9y ago
  There are some USB c complaince issues which are yes literally just the wrong resistor. What you're describing might go beyond that though, in particular if there's multiple ports and hubs involved, that could be not just a usb problem.

by dmoy 9y ago

fjsolwmv 9y ago

It's cost cutting to make cheaper cables and ports.

lvh 9y ago
Or intentional trivial incompatibility to sell _more expensive_ cables and ports :)
- gregmac 9y ago
  That's a scary possibility. Flood the market with barely-functional garbage in the low range so that consumers can't figure out which cheap ones are actually usable and just pay more to avoid the headache. It's not dissimilar to the box store HDMI/audio/etc cable strategy: Cheap, absolutely garbage cables at a mid-range price, or upper-mid-range cables at grossly over-inflated prices. Consumers tricked because of course the $200 HDMI cable looks noticeable better than the $20 one. Reality is the real retail prices of cables they're comparing should be more like $2 and $20, and the difference between that $20 cable and one that actually would cost $200 is only noticeable with high-end test equipment (or by 'audiophiles', who have the super-power of being able to see/hear a difference in cables as long as they know the price).

deleted 9y ago

[deleted]

deleted 9y ago
[deleted]

heisenbergs 9y ago

This was the case when the original USB came out first too. It took a good couple of years to mature. I think these are normal standardization issues...

Someone1234 9y ago
Difference is that when the original USB spec came out it wasn't delivering enough power to kill somebody, contrast that with today where a USB-C error could be fatal. See: https://www.theverge.com/2016/2/4/10916264/usb-c-russian-roulette-power-cords https://www.theverge.com/2016/2/4/10916264/usb-c-russian-rou...
- MisterTea 9y ago
  This is incorrect. The high power charge is 20 volts, below the safe threshold of ~50V set by such agencies as: OSHA, NFPA, ANSI, IEEE, UL, IEC and others. The real difference is USB was a completely new technology with zero market penetration so growing pains were inevitable. USB-C should not have these growing pains as they should have learned from 20+ years of developing the standard.
  - gok 9y ago
    There is relatively little risk of electrocution but 100 watts can still be more dangerous than 10 watts. Overheating and fire are a much bigger risk.
  - derefr 9y ago
    Is it really large, established manufacturers who are making these mistakes? Or is it random fist-time hardware entrepreneurs in Shenzhen? Analogy: we don’t blame Javascript-the-language-standard for the Node community’s constant (and usually half-assed) reinvention of build tools. Javascript itself didn’t cause that. More than likely, it was a glut of newbie developers joining the community—and building tools for one-another, rather than leaving it to the experienced people—that caused that.
    - 9y ago

Cthulhu_ 9y ago

Is it just a resistor, or is it one of hundreds of possible resistor depending on factor X? USB or any connection should be simple - you know, like code. The more exceptions and options you add, the harder it becomes to properly implement it. This is exponential, too, not linear.

TheSoftwareGuy 9y ago

>EEs who can actually read a damn spec sheet properly... I think this is the hardware equivalent of expecting programmers to write bug free code on the first try. Most of the time when a programmer wants to implement something a little complex and a little outside their expertise, they use an external library. Likewise, EEs will often buy a chip produced by a third party manufacturer and use that to handle it. But the abstractions available to EEs are often a bit more leaky than those available to us programmers, since they are more constrained by the laws of physics. and as a result that third party chip is still harder to use than a software library.

throwahey 9y ago
That is still an avoidable error. You shouldn't be adding parts without understanding how they work or how they will affect your circuit as a whole.
baddox 9y ago
On the first try? I would hope that hardware manufacturers don't take the engineers' first attempt and immediately go into mass production.
ChuckMcM 9y ago
That isn't the way EE's are trained in my experience. When new hardware is designed that is outside the EE's experience there is usually an evaluation board available from the manufacturer. They get one of those in house, read the application notes and data sheets, and use their test equipment to observe the 'proper' signal levels and waveforms on a correctly implemented system. Then they add this part to their design, and lay out the schematic and the printed circuit board according to best practices by the manufacturer. Once the first boards return they put measure the signal levels and waveforms in their circuit to verify they are with the specifications and that they match the ones on the eval board. Then they will 'corner' test the circuit (corners are low/hi temperature range, low and high voltage range) and verify it continues to work according to specification at all the 'corners' (if it does then you are generally ok with assuming it will work at all points "inside" those for corners.) There are people who are either in a hurry or don't care who wire something up according to the application note, power it up once and call it 'good'. I've seen a number of cost reduced 'clone' equivalents that meet that description. @kens has done a number of blog posts that show this sort of mentality in detail.

logicallee 9y ago

It must be more than "engineers can't read a spec" because decices using previous versions of USB tend to be fine. So why can engineers read those specs? (Why didn't they "choose an incorrect resistor value" for previous generations of USB, then?) This spec by contrast must be far more complicated[1]; also since it is so much faster, can't quality components supporting it all be more expensive - leading to cutting corners as a cost cutting feature? Also if as a consumer you can't predict what "should" be about to happen (which way power will flow, what will be host) that is down to a bad spec re connector types. For example couldn't a universal visual indicator on a port (including the bottom of a phone) indicate its capabilities and what will happen very clearly? (Through symbols.) They do not. Couldn't a software popup make you choose? They do not. Not to mention that it is not clear what should happen. If a phone can power a USB peripheral (like usb on the go) that means it could charge a second phone. So if you connect two phones which one should charge the other? With old versions of USB phones the answer is simple: whichever one you put an on the go converter into, making it a master instead of a phone's usual role as a slave. The fact that the spec does not make these as clear for USB C is down to the spec and design. Can't USV C simply be badly designed? (overdesigned, underdesigned, badly designed.) [1] Consider that a 1-page spec that can be read and implemented quickly in 15 minutes, can be implemented by anyone. A five-thousand page spec that takes 1,000 hours to read and understand can be implemented by no one (only teams). In between we have both previous versions of USB and USB C - but is it possible that USB C is too far in the latter direction?

daurnimator 9y ago
> Couldn't a software popup make you choose? They do not. They do when I e.g. connect two android phones together.
- logicallee 9y ago
  Got it (never tried it).

amluto 9y ago

A sane USB-C spec would not have required a resistor for an A-to-C cable.

kjdndisneinj 9y ago
A single resistor is seriously not challenging to get right. If they can't do that they sure as hell shouldn't be making a cable.
- amluto 9y ago
  Your average cable is some wire, some connectors, and plastic. Adding a resistor adds a whole extra element to the process, which is a big deal for a part that sells for probably well under $1 wholesale. Cable shops probably have no experience with circuits. The USB-C spec for some reason made it so that cables with no resistor or with the wrong resistor still seem to work but are unsafe. Of course the result is a mess.
  - tadfisher 9y ago
    Just about every video game console made between the late 1980s and mid-2000s had an official video-out cable with one or more resistors [1]. It's not an unheard-of thing. [1]: http://members.optusnet.com.au/eviltim/gamescart/gamescart.htm http://members.optusnet.com.au/eviltim/gamescart/gamescart.h...

ljm 9y ago

Is it really that simple? Just changing a resistor value? I got an XPS 13 for work, it’s all USB-C, and the versatility of the port is fantastic (doesn’t matter which port I plug into, it still charges, so I don’t have to wrap the power cable around the back of the machine or sit in a weird position to keep some slack in the wire). However, I took it to the office and naturally I plugged my power adapter into one port. I then plugged in the monitor (also USB-C, delivering power), and the two ports cancelled themselves out and confused the OS. Windows thought I was charging the laptop yet it also said the battery was depleting. They were negating each other and the battery loss continued as it would with no power connected. It makes sense for a monitor to power the laptop because it’s mains connected. But then you have one of those classic programming problems: if there are multiple inputs providing the same thing which do you consider the source of truth?

criddell 9y ago
They could always ask the user if they are that confused then remember the answer so they don't have to ask again.
- ljm 9y ago
  Can you imagine a typical laptop user who assumes everything 'just works' (like me, by virtue of thinking I need to power my laptop while attaching a powered monitor) seeing a prompt in the OS about which thing should provide power and which should either reject it or use it to charge a battery?
  - acct1771 9y ago
    Can you imagine someone not understanding a clearly worded UI that they use to do the things they have to do to function in society?
dmoy 9y ago
There are some USB c complaince issues which are yes literally just the wrong resistor. What you're describing might go beyond that though, in particular if there's multiple ports and hubs involved, that could be not just a usb problem.