[ntp:questions] Do I have a lock to my NMEA GPS?
David Malone
dwmalone at walton.maths.tcd.ie
Mon Nov 12 10:32:09 UTC 2012
Terje Mathisen <"terje.mathisen at tmsw.no"> writes:
>David Woolley wrote:
>> Terje Mathisen wrote:
>>
>>>
>>> I don't know exactly how much power it needs, but since it runs easily
>>> on USB power, it has to use less than 500 mA @ 5V (2.5W), and probably
>>> significantly less.
>>
>> If you are using Linux, you can use lsusb to find the declared current
>> consumption for the device, which should give you an upper bound on the
>> power consumption.
>FreeBSD, I don't know if that OS has something similar?
You can do something like this, I think:
usbconfig -d ugen1.4 dump_all_config_desc | grep -i power
It gives you a value in hex, something like this:
bMaxPower = 0x00fa
Which, I think, is the max current in 2mA units. 0x00fa is 250, or
500mA.
David.
More information about the questions
mailing list