free hit counter

Thursday, September 28, 2006

Making the switch to Linux

I've been talking about it forever, but now that I have a space PC, Amy's old laptop, I'm making the switch.

Looks like a dual boot Ubuntu / XP. It'll be real tight with the 20 gb disk

LinuxDevCenter.com -- Creating a Dual-Boot Windows XP and Ubuntu Laptop

Monday, September 25, 2006

calculate a percent difference

why do I always blank on this?


calculate a percent difference: "percent difference between a known value A and a calculated value B is:

|A - B|
% dif = ------- * 100%
A

In our example, A = 12; B = 12-2*.001148. so their difference, A - B, is simply 2*.001148 and hence percent difference is:

|2*.001148|
% dif = ----------- * 100% = 0.019 %
12

Less than 5% so the assumption that x was negligibly small is good."

linkage

Friday, September 22, 2006

not out of the box: Open GL texture mapping

Monday, September 18, 2006

DIY RAID NAS

Friday, September 08, 2006

gettin crazy with the VBA

crazy spreadsheet action around here. A pair of VBA functions to go through several formated child sheets to generate a plain text (data filterable) summary.


Sub Summarize(aSheetName)
'
' Summarize Macro
' Macro recorded 9/8/2006 by rsanderson
'

Sheets(aSheetName).Select
Range("C8").Select

Do
'copy the current cell and its east neighboor
Range(ActiveCell.Offset(0, 0), ActiveCell.Offset(0, 1)).Select
Selection.Copy

'paste into the summary sheet
Sheets("Summary").Select
ActiveCell.Select
Selection.PasteSpecial Paste:=xlPasteValues, Operation:=xlNone, SkipBlanks _
:=False, Transpose:=False


'move to the next col in the summary sheet to prep for next data in this row
ActiveCell.Offset(0, 2).Select

'go back to original sheet and copy the other three cols
Sheets(aSheetName).Select
Range(ActiveCell.Offset(0, 23), ActiveCell.Offset(0, 25)).Select
Selection.Copy

'paste into the summary sheet
Sheets("Summary").Select
Selection.PasteSpecial Paste:=xlPasteValues, Operation:=xlNone, SkipBlanks _
:=False, Transpose:=False

'move to next row to wait for next paste command on the summary sheet
ActiveCell.Offset(1, -2).Select

'change back to orignal sheet and go to next candidate cell
Sheets(aSheetName).Select
ActiveCell.Offset(3, -23).Select


Loop Until IsEmpty(ActiveCell)

Sheets("Summary").Select

End Sub
Sub summarizeAllRegs()
'
' Macro written 8/2006 by rsanderson
'
' Keyboard Shortcut: Ctrl+p
'
Summarize ("System Commands")
Summarize ("SV02 Commands")
Summarize ("Pressure Commands")
Summarize ("FW Commands")


End Sub

Labels:

Wednesday, September 06, 2006

HD44780 parallel LCD displays

Good resources for HD44780 LED displays.

HD44780-based LCD Modules

Labels:

makefiles for Xilinx webpack tools

The Xilinx webpack tools are great except they don't support command line builds out of the box.

These scripts look like at best a turnkey solution, at worst a good starting place

MAKEFILES FOR XILINX FPGA/CPLD PROJECTS

Labels:

Friday, September 01, 2006

GPL Infection?

Here's a great two page artical which distills fears about "GPL infection".

http://www.informationweek.com/story/showArticle.jhtml?articleID=162100717&tid=5979

An interesting point it brings up is that an API or DLL can insulate you from "infection"