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Permalink Reply by James Hall on January 17, 2008 at 7:13pm

The schematic looks pretty simple. What don't you understand?

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Permalink Reply by Simon Pan on January 17, 2008 at 7:27pm

Well I mounted it on the breadboard, but I can't tell which pins are which. The orientation of the text on the actual thing is different from the schematic.

http://i137.photobucket.com/albums/q224/skatj/breadboard.jpg

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Permalink Reply by James Hall on January 17, 2008 at 7:35pm

Mount the IC so that its center over the middle slot on the breadboard. Then start hooking up wires.

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3D RoboticsPermalink Reply by Chris Anderson on January 17, 2008 at 9:36pm

Yikes. James is right. Don't connect any pins until you understand how breadboards work. All the holes on each side of the center line are electrically connected. The chips HAVE to straddle the center line or you're going to fry them.

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Permalink Reply by Simon Pan on January 17, 2008 at 10:20pm

Alright alright thanks.

One problem though, I still can't tell which pins are which (orientation of the text is different from the schematic, is there some kind of accepted standard that I don't know about?

Oh, and what do the green circles mean in the schematic?

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3D RoboticsPermalink Reply by Chris Anderson on January 17, 2008 at 10:33pm

All ICs have a little half-circle indent on one end. With that at the 12 o'clock position, pin #1 is the first on the left and the numbers go counterclockwise from there. You should be able to correspond that to the first diagram in the documentation you linked to.

The green circles mean that lines are electrically connected (rather than just crossing over each other in the diagram). So in the first example, both pin 1 and 4 are connected to ground.

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Permalink Reply by Simon Pan on January 18, 2008 at 10:45am

Thanks Chris, I found the indent.

My mom's an electrical engineer but she doesn't know the english words for anything =(

I took a shot at it last night, please let me know if it looks right.

http://www.project-uav.net/images/FPUinterface.jpg

I had to take the picture with a webcam and the lighting was really bad. I tried to retouch it in photoshop but it didn't help much, so sorry for the quality.

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3D RoboticsPermalink Reply by Chris Anderson on January 18, 2008 at 10:54am

that looks like a good hookup. Not sure what the wires go to (or should go to--I've never used that chip), but it looks like you've got the hang of breadboard assembly.

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