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USB ports on Laptops

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(@armresl)
Posts: 1011
Noble Member
Topic starter
 

I'm curious if any of you, maybe more importantly how many of you have issues with your USB ports and connecting phones to them.

Not talking about for charging purposes, I know there is a lack of proper voltage issue on most.

More to the point, intermittent accepting the phone then losing the connection, wash, rinse, repeat.
Cords are varied as are the ports. OS is 7 and 8.1.

Also, not having to do with type of connection, MTP, file transfer, MIDI, etc.

Thanks.

 
Posted : 06/06/2018 6:49 pm
(@mcman)
Posts: 189
Estimable Member
 

You sure it's not a software issue? Drivers, VID/PID, etc…? I know Windows tends to fumble with this especially since each method uses a different driver so you could have 6 different drivers used for a given phone. Some methods need to flip between different drivers in the middle of the process which can cause issues too.

I know I often have to blow away drivers and such to get some things to work if I'm messing around with them too much.

Jamie

 
Posted : 06/06/2018 7:52 pm
(@armresl)
Posts: 1011
Noble Member
Topic starter
 

Not sure of much, just trying to get a feel into issues people are running into.

Interestingly enough, when I was working onsite, a kind Detective mentioned to me that they employ a jiggler because Win 10 frequently took no mouse movement as an issue and changed power to the USB ports accordingly.

I already adjusted the power when I first got the laptop along with the usual "show hidden" etc.

You sure it's not a software issue? Drivers, VID/PID, etc…? I know Windows tends to fumble with this especially since each method uses a different driver so you could have 6 different drivers used for a given phone. Some methods need to flip between different drivers in the middle of the process which can cause issues too.

I know I often have to blow away drivers and such to get some things to work if I'm messing around with them too much.

Jamie

 
Posted : 06/06/2018 8:09 pm
(@armresl)
Posts: 1011
Noble Member
Topic starter
 

Sorry Jamie, meant to add let's act like there is nothing going on with the PC, just that it is plugged in with a phone to any of the USB ports.

You sure it's not a software issue? Drivers, VID/PID, etc…? I know Windows tends to fumble with this especially since each method uses a different driver so you could have 6 different drivers used for a given phone. Some methods need to flip between different drivers in the middle of the process which can cause issues too.

I know I often have to blow away drivers and such to get some things to work if I'm messing around with them too much.

Jamie

 
Posted : 06/06/2018 8:10 pm
Passmark
(@passmark)
Posts: 376
Reputable Member
 

I'm curious if any of you, maybe more importantly how many of you have issues with your USB ports and connecting phones to them.

Not talking about for charging purposes, I know there is a lack of proper voltage issue on most.

Actually the voltage levels are not normally the problem. We've checked 100s of ports. It is rare that the voltage is too far out of specification, unless the cable is very long.

What is an issue the current (Amps) being made available. Of the years there have been lots and lots of different USB standards.

In the USB 1.0 specs, a standard downstream port is capable of delivering up to 100mA at 5Volts, over 4 wires. (Two data wires, +5V and ground).

In the USB 2.0 specs, a standard downstream port is capable of delivering up to 500mA at 5Volts, again over over 4 wires. (2.5 Watts) once a device is enumerated. The limit is just 100mA prior to enumeration.

USB 3.0 ports add an additional row of five pins to make a total of nine wires. They are also able to supply more current. There are three kinds of USB port dictated by the 3.0 specs (and another specification known as the Battery Charging Specification, BC1.1 and then BC1.2)
- A standard downstream port (SDP). Found on most computers, with a current limit of 500mA before enumeration and 900mA after enumeration.
- A charging downstream port (CDP). Found on some computers, 1500mA (1.5A, 7.5W)
- A dedicated charging port (DCP) for "dumb" wall chargers, also allowing 1500mA (1.5A, 7.5W)
The USB 3.1 specification ports support 1.5A and 3A at 5V.

With the Type-C connector the USB power delivery specification was also introduced, which allows power transfers of up to a massive 100W at varying voltages. The combination of a voltage level and current limit was referred to as a "profile".
- Profile 1 (Default) 10 W (5 V @ 2 A)
- Profile 2 18 W (5 V @ 2 A -> 12 V @ 1.5A)
- Profile 3 36 W (5V @ 2 A -> 12 V @ 3A)
- Profile 4 (Micro B/AB limit) 60 W (5 V @ 2 A -> 20 V @ 3 A)
- Profile 5 (Standard B/AB limit) 100 W (5 V @ 2 A -> 20 V @ 5 A)

With Type-C a good cable is especially important.

In the early days of USB there was a *lot* of device driver and firmware bugs. Especially around power management. But it has got a lot better in recent years.

It is also relativity easy to blow up USB ports, by doing things like shorting out the data lines to ground. Or shorting the low voltage data lines to the higher voltage V+ line. We have several machines with one or more dead USB ports.

The other big problem we see is just mundane electrical connection issues. Either the delicate connector is slightly loose and bent out of shape or the metal contacts on the connector are corroded. We especially see the corrosion issue on front USB ports where the air flow in the PC case is front to back. Meaning the connectors tend to accumulate dust.

 
Posted : 06/06/2018 11:53 pm
(@armresl)
Posts: 1011
Noble Member
Topic starter
 

Thanks Passmark, I meant amps.

So taking the cord out of the mix, you are thinking USB 2 ports may have a bigger problem than USB 3 ports?

How about certain phones, say Iphone vs Hu's or ZTE?

I'm curious if any of you, maybe more importantly how many of you have issues with your USB ports and connecting phones to them.

Not talking about for charging purposes, I know there is a lack of proper voltage issue on most.

Actually the voltage levels are not normally the problem. We've checked 100s of ports. It is rare that the voltage is too far out of specification, unless the cable is very long.

What is an issue the current (Amps) being made available. Of the years there have been lots and lots of different USB standards.

In the USB 1.0 specs, a standard downstream port is capable of delivering up to 100mA at 5Volts, over 4 wires. (Two data wires, +5V and ground).

In the USB 2.0 specs, a standard downstream port is capable of delivering up to 500mA at 5Volts, again over over 4 wires. (2.5 Watts) once a device is enumerated. The limit is just 100mA prior to enumeration.

USB 3.0 ports add an additional row of five pins to make a total of nine wires. They are also able to supply more current. There are three kinds of USB port dictated by the 3.0 specs (and another specification known as the Battery Charging Specification, BC1.1 and then BC1.2)
- A standard downstream port (SDP). Found on most computers, with a current limit of 500mA before enumeration and 900mA after enumeration.
- A charging downstream port (CDP). Found on some computers, 1500mA (1.5A, 7.5W)
- A dedicated charging port (DCP) for "dumb" wall chargers, also allowing 1500mA (1.5A, 7.5W)
The USB 3.1 specification ports support 1.5A and 3A at 5V.

With the Type-C connector the USB power delivery specification was also introduced, which allows power transfers of up to a massive 100W at varying voltages. The combination of a voltage level and current limit was referred to as a "profile".
- Profile 1 (Default) 10 W (5 V @ 2 A)
- Profile 2 18 W (5 V @ 2 A -> 12 V @ 1.5A)
- Profile 3 36 W (5V @ 2 A -> 12 V @ 3A)
- Profile 4 (Micro B/AB limit) 60 W (5 V @ 2 A -> 20 V @ 3 A)
- Profile 5 (Standard B/AB limit) 100 W (5 V @ 2 A -> 20 V @ 5 A)

With Type-C a good cable is especially important.

In the early days of USB there was a *lot* of device driver and firmware bugs. Especially around power management. But it has got a lot better in recent years.

It is also relativity easy to blow up USB ports, by doing things like shorting out the data lines to ground. Or shorting the low voltage data lines to the higher voltage V+ line. We have several machines with one or more dead USB ports.

The other big problem we see is just mundane electrical connection issues. Either the delicate connector is slightly loose and bent out of shape or the metal contacts on the connector are corroded. We especially see the corrosion issue on front USB ports where the air flow in the PC case is front to back. Meaning the connectors tend to accumulate dust.

 
Posted : 07/06/2018 3:23 am
(@mcman)
Posts: 189
Estimable Member
 

Sorry Jamie, meant to add let's act like there is nothing going on with the PC, just that it is plugged in with a phone to any of the USB ports.

Passmark's remarks are good, we do a lot of automated testing where we leave devices plugged in for long periods of time (days) and continually acquire them and while hit the occasional snag, most of the time it works fine as long as the computer is configured correctly (same settings as you've indicated).

I'll check with our guys who run the tests to see if they know of any quirks on specific devices or models.

Jamie

 
Posted : 07/06/2018 1:24 pm
(@mcman)
Posts: 189
Estimable Member
 

Checked with the team and they did say they often ran into issues where ADB would disable itself on Android devices either after too much time or too many commands sent through (they weren't sure on the exact criteria) but unplugging and plugging back in solved the timeouts or whatever the cause was.

Jamie

 
Posted : 07/06/2018 2:59 pm
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