I am a novice to electronics and micro-controllers.
I am also a novice to programming in C though I have programmed plugins for 3ds Max in maxscript which seems pretty similar.

My project involves programming My Canon Camera via a USB host
similar to this project:

It also involves a number of sensors that use SPI bus
and some that Use I2C
I wanted also to use a LiPO battery to charge while plugged in and then discharge when in use
Finally I plan to use e-paper as output device with some LED's to light my project in low light.

I was planning to use the Mini PRO 3.3v as the basis for this project, mainly because a USB Host Shield is available for it.

But I cannot find a suitable Module for charging the LiPo that automagically switches to powering the project when not plugged in without the need for multiple USB sockets on the one device.

I am still researching all the sensors I need, but my other concern is powering all of the peripherals on the various buses.
Is the Trinket pro a better choice?


Hi, just used Google. "usb charging ic"

Not sure if it helps, but there is stuff out there.

Tom... :slight_smile:

Thanks for the response. I did get some cheap lipo chargers on EBay that seem to be able to do the trick.
however I have run into a ton of other problems. I was thinking I should start a new thread considering that my first response was so nebulous. I hope you don't mind. But I get the feeling that people didn't really know what I was asking.

I only saw one question:

Is the Trinket pro a better choice?

Maybe if you read this it might answer your question.

I'd suggest that anyone wanting to interface to a cannon camera should become conversant with the magic Lantern project. Likely as not, it will simplify just about anything you want to achieve.