Arduino Uno rev. 3:
As far as I can see there is no power on the USB connector when powering Arduino through the power connector. Is there a way to achieve this?
(I want to connect a GPS_unit to the USB port and it needs power through its USB jack.)
Are You sure the GPS can work as master and send any data through the USB? Why not use a USB powerbank for the GPS? I do that, powering both an UNO and the GPS.7
If space is a challenge you could also hack a USB port together by connecting the 5v / ground wires from the Arduino circuit into a USB jack you splice. you could also get a cable that has a motherboard header on one end, usb connector on the other, and connect to the Aruduino circuit? As long as the GPS just needs power and NOT data I assume. I would put some sort of capacitor before the USB output too. But I don't know what the GPS wants.
How do You power the Arduino using the barrel jack? Using what source?
Are You sure the GPS can work as master and send any data through the USB?
The GPS-module has one connector, only; a male USB A-type. It sends its NMEA-data via that USB when connected to a pc (virtual com port) and is powered from the very same USB connection.
How do You power the Arduino using the barrel jack? Using what source?
I use a 230V to DC 9V/300 mA adapter.
Okey. The GPS connects to a Pc USB. Then it will not work to connect it to an Arduino. The Arduino and the GPS are of the same kind, "slaves" while a Pc is a "master".
You'd have to modify the board to connect 5V from the power header (or other 5V pin) to the USB connector 5V pin.
You will only get power the. The USB port does not support being a USB master. Set up software serial on a couple of pins to talk to the GPS.
The transistor here keeps 5V from backfeeding into the USB/PC, so you need bypass it.
Thank you for those clarifications.
Best regards,
Niels
The transistor here keeps 5V from backfeeding into the USB/PC, so you need bypass it.
Would you be so kind as to show me from where to where on the diagram? Just to be sure.
Thank you in advance.
Why not just add a USB loose socket to the 5V supply?