Re: [Paparazzi-devel] New Autopilot board, lia/lisaM fork.

[Piotr Esden-Tempski]

Hi,

A few random comments.

On May 12, 2013, at 8:59 AM, address@hidden wrote:

> I´m have done LIA, it´s  near complete. Now i´m beginning with LISA, same 
> size of LIA, bigger as actual lisaM.
> Do you have other wishes ? Is someone on the list willing to test the board ?
>  
> Differnces to previous LIA:
> MPU-9150 footprint inside ASPIRIN footprint.
Don't forget baro. And also be careful with that ... please don't bring back 
the i2c nightmare! Also reading out all the sensors with i2c will be probably 
at least on the verge of impossibility and will force you to use the invensense 
motion engine. Consider designing towards MPU-9250.

> PA6H GPS module including external Antenna added.
> Xbee socket added.
I have not seen your design. But that sounds like a big space waste on the 
board.
> possibly to reflow micro-SD card on the pcb.
Good idea. Think about manufacturability...
> Improvements on powering section.
What does that mean? :)
>  
> TODO:
> remove USB connector.
Why?
> add usb protection circuit.
What do you mean? If you mean ESD protection, then I think that is totally 
unnecessary in this application and just waste of space and weight. If you mean 
reverse voltage protection, please elaborate.
> Added RS485 as lower cost bus option or instead of can
I hope you mean ADD and not replace. CAN vs RS485 transceiver price difference 
is almost negligible. About 4cents a peace at 100 pcs... having a well defined 
protocol with filtering options and built in collision avoidance vs a custom 
protocol is in my opinion a better choice in most cases. But correct me if I am 
wrong.

As I did not see your designs take my comments with a grain of salt. :) Sorry 
if I missed a link to your github or something. Are you putting them somewhere?

Good luck with your project.

Cheers Piotr