Previously, I’ve picked up several transistors as candidates to be used for noise source for noise generator.

https://gaje.jp/2014/01/14/2915/

I’ve started testing these transistors.

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This works for windows.

http://stackoverflow.com/questions/12175964/python-method-for-reading-keypress

However, you cannot use this feature from cygwin.  You need to invoke python script directly from Windows.  Double-clicking the python script works, but you need to catch exceptions in the case (otherwise, you don’t know what happened when an exception was raised).

Here is the sample program to read arrow keys.

#!c:\Python32\python

from msvcrt import getch
import sys

print("press ESC to exit")

while True:
    try:
        key = ord(getch())
        if key == 27: #ESC
            break
        elif key == 224: # special keys (arros, f keys, ins, del, etc.)
            key = ord(getch())
            if key == 75:
                print("left")
            elif key == 77:
                print("right")
            elif key == 80:
                print("down")
            elif key == 72:
                print("up")
    except:
        print(sys.exc_info()[0])

This link helped

http://stackoverflow.com/questions/307305/play-a-sound-with-python

I’m working on Windows, so winsound worked.  It was as simple as

#!/usr/bin/env python

import winsound

winsound.PlaySound("ex1.wav", winsound.SND_FILENAME)

As mentioned in my previous post, AVI Dragon’s SPI pins in debugWire interface have to be disconnected during debug run in order to properly run an application that uses SPI / USI.  I also noticed that the Dragon dominates RESET pin, too.  In my project, I’m resetting target chip from Arduino.  The Dragon is killing this functionality as well.  This makes me quite uncomfortable with my development work, so I’ve enhanced the switch I made on bread board previously, and made a helper device.  It’s nicely working.  I named it “Dragon’s Tail”.

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