USB Feed

Hello guy I was thinking about a thermometer powered by my USB. Just like this gadgets we see every time. Do you guys think the USB can power a picaxe?

If so, how do I do that?

Cheers

 

I think some people (or Rev-Ed? I can't remember) have done some work with the FT232.
Maybe have a search on it.

Have a look at the circuit in the AXE027 USB download cable datasheet.

www.rev-ed.co.uk/docs/axe027.pdf

You could power PICAXE circuit aswell as long as the total current drain is less than 100mA.

Sounds good to me... Do you think 100mA is enough for a picaxe, 2 LED009(7 segment display) and a DS18B20?

Cheers

 

a little warning with usb ports... even though the standards say that a usb port should be capable of supply X amount of power

what they are actaully capable of is usaully a different story... i have come up to a few that had trouble powering an optical mouse that was trying to draw 80ma

it is a lot safer to use a powered usb hub as most of them can supply up to 500ma and even in some cases 1 whole amp

your other option is to make up a cable and provide power externally through the usb cable without drawing power from the port...do a google search

they are really only good for mice, keyboards and webcams at a push

In general a USB port (providing anything up to 500mA) will easily power a light duty Picaxe (which draws ~ 3mA itself). It's the associated LOAD that needs considering however! A few LEDs will be a breeze, but motors, relays etc will often demand more than the USB port can deliver...

Far more important IMHO is that a US$500 PC has to be always on for the Picaxe task,- this may be equiv. to a sledgehammer cracking a nut.

we tried that once it's not that easy to hit a nut with a sledge hammer especially when ur drunk... mhy brother in law missed the nut and broke a paver