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I have stripped down a very early (2002) vaio all-in-one desktop which has a keyboard with a built in protective cover which I would really like to use on another computer. The dongle was placed under a cover on the outside of the casing and has the rating 5v 100ma on the back. The cable was designed to go straight to a connector on the mainboard and appeared to be USB, I adapted a usb cable to connect but when I plug it in the dongle has too high amperage and windows complains. Is there anything I can do to enable this to connect? The device is seen by windows but cannot power it.

CN2 is for a connect button, CN1 is USB from bottom, Ground data(+) data(-) +5v

view front and rear vgp-wrc1/b

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  • \$\begingroup\$ When you say, "This device is seen by Windows", are you saying that it recognizes the device as it is? If not, then how do you know this device is compatible with the hardware? \$\endgroup\$ – user103380 Feb 25 '18 at 17:41
  • \$\begingroup\$ What is your "another computer"? Does it have full normal USB port? Did you try to attach the RF dongle to any other computer port? Also, the pins on the left are likely "shield", "gnd" "D+", "D-", "VBUS". You missed the "shield". Also, what windows is complaining about? Why do you omit all these details when asking a question? \$\endgroup\$ – Ale..chenski Feb 25 '18 at 18:36
  • \$\begingroup\$ How did you determine that "the dongle has too high amperage"? \$\endgroup\$ – Ale..chenski Feb 25 '18 at 18:49
  • \$\begingroup\$ I'm only going on what the pop-up said within Windows 10 - USB device requires more power than the port can supply - Device is rated at 5v so I am assuming the amps are not 100ma as on the ID sticker \$\endgroup\$ – JohnnyVegas Feb 25 '18 at 21:26
  • \$\begingroup\$ This is strange. If Windows says "not enough power", it means that the device has started enumeration (so the USB interface is fine) and reports something above the sticker. Unless you have an overcurrent (really a lot of current, 2-3A), systems don't measure actual port consumption. It is very unlikely that Sony internal descriptors report more than 100 mA as the label states, and you should have a really weak (battery-powered) USB host that is declared as "low-power" host and rejects devices with >100 mA reported requirement. Strange, unless the Win says something different. \$\endgroup\$ – Ale..chenski Feb 27 '18 at 1:17
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Assuming that your device is actually recognized by Windows as a HID-Keyboard and is overcurrent for the port.

The default HID drivers and the OEM extensions define the parameters (including current allowed). See here for a good starting description.

One way you might get around your problem is to use a 1 port Hub/extension cable or a non-powered Hub between your device and the computer. The Hub is by default 100 mA (or 500 mA in some cases) so the computer port is configured for that amount of current (check the error you get in Device Manager).

There are many cheap non-powered Hubs available, for example an active extension cable like this or a non-powered Hub like this.

The USB system is configured from the Root out, so with a Hub in the cable the computer port is configured to allow the current defined by its descriptors.

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  • \$\begingroup\$ I would guess that the OP connected the cable ground to shield pin, which goes to ground via a resistor R4. As result, all USB signals are screwed, and Windows fails to enumerate the device. The OP however falsely assumed that the problem is in power. \$\endgroup\$ – Ale..chenski Feb 25 '18 at 18:53
  • \$\begingroup\$ @AliChen. Maybe. \$\endgroup\$ – Jack Creasey Feb 25 '18 at 19:18
  • \$\begingroup\$ Will try the USB hub route, but I think Ali may have a point with the cable - Will make one from scratch rather than using an old USB cable. \$\endgroup\$ – JohnnyVegas Feb 25 '18 at 21:28

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