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Atmel AT91SAM7S, ARM7TMDI, OpenOCD and Olimex SAM7-H256 Doc Compilation
A document compilation for a recent purchase of an Olimex SAM7-H256 from SparkFun, an Atmel AT91SAM7S256 based breakout-header dev-board. Includes relevent manuals, datasheets, application notes, and example files from Atmel, ARM, the OpenOCD project, and board descriptions of the Olimex header board.
bzip2 compression was used to decrease file size from 100MB+ to only 35MB.
Posted by rmrubin 
Posted in: Programming, Electronics 
Comments Off 
December 2007
AVR Synther ADSR Plan B: Success.
Flowcharts are neat. ADSR now works. Gain is exponential on all slopes. Planned adjustments include gain table increase from 256×16 to 1024×16, with a linear ramp mode for the attack mode. 8bit and 16bit output varients planned. Scope image is from a Tektronx 2230 in DSO mode using the Roll mode (as opposed to Scan) for capture of very long waveforms (greater than 3 seconds).
Posted by rmrubin Posted in: Programming, Electronics Comments Off December 2007
AVR Synther ADSR Gain Envelope. Plan B…
Flowchart for the ADSR gain envelope code, done in Dia.
Posted by rmrubin Posted in: Programming, Electronics Comments Off December 2007
“Hello World” is Lame. My First C App, “inthetriangle”.
At some point, it was realized learning C is something that needs to be done before trying out anything ARM core based. Learning on an AVR, after already knowing how to do things competently on the microcontroller in ASM, was frustrating as it for the most part seemed pointless, introducing a whole other layer of issues that came with the compiler and had nothing to do with the hardware itself. Something tiny was written to test the WinAVR installation, then something better to do was found.
Then the other night, a friend came over and said his C class and the instructor didnt have a working algorithm to find if a test point was within a triangle. So I stared for awhile, convinced it didnt take very complex math to figure it out. The algorithm involved calculating the points that a horizontal line passing thru the test point intercepts the triangle sides (using slope equations and a difference equation) and testing if the test point is between these points. I decided I wanted to code my algorithm in C.
So here is the end result. My first C app, inthetriangle, will indicate if a point is on, within, or outside of a triangle. It will also indicate if the triangle points are invalid because of repeated points or if they actually describe a line segment. Input with scanf() is decidely ghetto. I’ll have to change that.
Posted by rmrubin Posted in: Programming Comments Off September 2007