Society of Robots - Robot Forum

General Misc => Misc => Topic started by: Admin on July 16, 2011, 03:54:48 PM

Title: about 3.3V microcontrollers (do you have concerns?)
Post by: Admin on July 16, 2011, 03:54:48 PM
The new soon-to-be-released Axon Mote, using 3.3V, has caused some controversy.

To find out more, see here:
http://www.societyofrobots.com/robotforum/index.php?topic=12650.120 (http://www.societyofrobots.com/robotforum/index.php?topic=12650.120)

If you have concerns about 3.3V, post it here and I'll do my best to alleviate (or confirm) your fears :P
Title: Re: about 3.3V microcontrollers (do you have concerns?)
Post by: joe61 on July 16, 2011, 04:02:21 PM
I confess I'm not entirely sure what the Mote is for quite yet, but I'm guessing that the row of three-pin connections are for servo/pwm type devices?

I'm interested in building something like this http://www.youtube.com/user/RyanPololu?blend=2&ob=5#p/u/1/-27CQ_d7YSg (http://www.youtube.com/user/RyanPololu?blend=2&ob=5#p/u/1/-27CQ_d7YSg)

However, I'd like to be able to have a few of these around the room, and control them from a base station with a T.V. remote, using an XBee controller. I like the Mote for this because of its wireless capability, but I'm not sure if 3.3 volts will be enough to drive the LEDs? Being that I'm Not Qualified as an engineer, is this actually a problem?

Thanks

Joe
Title: Re: about 3.3V microcontrollers (do you have concerns?)
Post by: Admin on July 16, 2011, 04:54:14 PM
I confess I'm not entirely sure what the Mote is for quite yet, but I'm guessing that the row of three-pin connections are for servo/pwm type devices?
You can find detailed info on the pins here:
http://www.societyofrobots.com/axon_mote/axon_mote_datasheet.shtml (http://www.societyofrobots.com/axon_mote/axon_mote_datasheet.shtml)
(rough draft at the moment)

Quote
I'm interested in building something like this http://www.youtube.com/user/RyanPololu?blend=2&ob=5#p/u/1/-27CQ_d7YSg (http://www.youtube.com/user/RyanPololu?blend=2&ob=5#p/u/1/-27CQ_d7YSg)

However, I'd like to be able to have a few of these around the room, and control them from a base station with a T.V. remote, using an XBee controller. I like the Mote for this because of its wireless capability, but I'm not sure if 3.3 volts will be enough to drive the LEDs? Being that I'm Not Qualified as an engineer, is this actually a problem?
You will need to look at the datasheets for your LED's + electronics. The RGB LED Satellite Module 001 in the video "requires 9 to 10 VDC at 100mA", so you need an LED driver to use it. This will be a problem even with 5V microcontrollers. You just need to find an LED driver that accepts 3.3V commands (the ShiftBar driver in the video requires 5V).
Title: Re: about 3.3V microcontrollers (do you have concerns?)
Post by: joe61 on July 16, 2011, 08:03:35 PM
I've got a couple of these http://www.sparkfun.com/products/8745 (http://www.sparkfun.com/products/8745) lying around, maybe I could use those somehow.

I'll take a look at the link you sent.

Thanks

Joe