Saturday, May 28, 2011

VHDL implementation compared to MATLAB model - overall success

Overview of successful results with synthesizeable VHDL implementation.
Comparison with MATLAB results.
-Michelle W5NYV

Thursday, May 19, 2011

"What's Up With ARM"

Here's an opinion piece about the current state of Linux development on ARM. I
thought it was interesting, largely agree with the author, and wanted to share
it with you guys.

Having got the beagleboard lab back up and running after the extended tour of
duty doing VHDL, I find that it is very true that getting Linux working on ARM
can be much more "some assembly required" than, say, a desktop. It's well worth
it, considering how powerful the ARM family is.

In order to develop something useful for MEP on ARM, there is quite a bit of
slogging to do through various rough edges. When experimenting with cameras and
video output, nothing ever really "quite worked", and the variety and
duplication mentioned in the article were in full evidence.

The current Angstrom build I'm working with was obtained from the Narcissus
Angstrom image builder. I used this because I simply could not get the demo
build of Angstrom to cleanly update from the package server. This sort of
obstacle can be really frustrating.

Here is the link to generate a build of Angstrom:

This image boots, but I haven't gotten much farther than launching Firefox.

More soon!
-Michelle W5NYV

Monday, May 9, 2011

updated synthesizeable VHDL block - progress

Here is updated VHDL code for the IQ Gain and Phase Correction filter.

I'm working with an adjusted numbering scheme in signed arithmetic to correct an
overflow problem (thanks to KB5MU, who helped identify). 

This implementation, which is designed to be synthesizeable, is beginning to
function as intended. There is a factor of two error, but the compiled block
outputs I and Q.

With some data visualization, these might prove to be a passed-through I and
phase corrected Q at the output, with a massive gain overcorrection. I'll check
that tomorrow!

 -Michelle W5NYV