install wifi and xpt2046 to raspi 1B+

RTL8188FU
XPT2046

sudo rpi-update

sudo wget http://downloads.fars-robotics.net/wifi-drivers/install-wifi -O /usr/bin/install-wifi

sudo chmod +x /usr/bin/install-wifi

sudo install-wifi

sudo reboot

plgsekip@my-Vostro:~/Downloads$ wpa_passphrase HOME HomeSweetHome
network={
    ssid="HOME"
    #psk="HomeSweetHome"
    psk=cc7724fc84fc63842fe458ac8e47ce2a59684327b698fc53758bc56a6eb90b53
}

copy this output to /etc/wpa_supplicant/wpa_supplicant.conf

edit /etc/network/interfaces

auto wlan0 

iface wlan0 inet dhcp 

wpa-driver wext 

wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

sudo reboot

https://www.elecrow.com/wiki/index.php?title=3.5_Inch_480x320_TFT_Display_with_Touch_Screen_for_Raspberry_Pi

git clone https://github.com/Elecrow-keen/Elecrow-LCD35.git

cd Elecrow-LCD35

sudo ./Elecrow-LCD35
 

Installing CVXOPT

1. Install Microsoft Visual C++ Build Tools

2. Install Intel Math Kernel Library

3. Install Python 3.6 (currently supported by cvxopt)

4. Install Python MKL --> Use PIP

5. Install numpy, scipy, cvxopt

Latest Update of My LM1875

Well, LM1875 is an interesting chip to play with. The number of components are so few that it is easy to build and less expensive if boutique components are to be used. I have bought complete Takman metal film resistor sufficient enough to build the amp, however, a friend of mine argued that I should use carbon film and he recommended his Allen-Bradleys for R-in and R-feedback of 22k. So in January 2015, I built the amp using combination of Takman REY 1k and two A-B 22k per channel. The result was satisfactory, but hey, I am still a human and never gets satisfied. :-D

So after these eight months of listening to A-B and Takman (carbon and metal film), it's time to rebuild the amp. This time, all resistors must be of Takman Rey Metal Film. PSU stays the same only swapping all the carbons with metal films.

In this setup, I replaced all carbon resistors previously used (those were Allen-Bradley) with metal film of Takman REY. PSU uses 2 x Nichicon FineGold 2200 uF and snubberized with 2 x ( Dale wirewound 0.47 ohm + WIMA FKP 220 nF ).

 For this system setup, I use LAN Cable Cat. 6 as I had access to the used ones. I can not comment on how this setup differs from or whether this sounds better than any other cables because I do not have those other so-called audiophile cables. :-)
My suggestion on using this twisted pair cable is to separate the twisted pairs. We can see that each pair consists of solid color cable and its pair with with color. Just aggregate all solid color cables into one and their respective pair into another one.

Where is Python in Solaris Studio 12.4 ?

I've been using Solaris Studio for quite some time and it is newly installed in my new Lenovo G40-SID. It was surprising that yesterday I noticed its different appearance compared to 12.2 version. Moreover, no more Python plugin is there! After reading here and there, I found Python plugin is no longer supported by Netbeans (the parent of Solaris Studio).

In order to enable Python plugin into Solaris Studio, I downloaded the Python plugin for Netbeans from here. After downloading and extracting the package, I opened my solaris from terminal.

$solstudio &

From Solaris Studio, go to "TOOLS" and then "PLUGINS" and from the plugins dialog, click on "DOWNLOADED" tab.

And then, point to the extracted folder of Python Netbeans Plugins and select all plugins and the install them.

Done !

Python User-wide Installation on CPanel Platform

Objective:

To run a python script with Numpy and Scipy from a web server hosted on a CPanel Hosting Provider.

Problem:

1. CPanel is using Python 2.6.6, hence older version of Numpy and Scipy installed do not agree with the previously developed program under Python 2.7.x and newer Numpy and Scipy.

2. Web hosting does not allow system-wide upgrade of the Python because this upgrade will affect the operating system's certain functions.

Proposed Approached:

User-wide installation of Python and other supporting libraries

Limitation:

User must be allowed to make secure shell connection to the server in order to install

Installation Procedures:

1. Download Python

    mkdir ~/python

cd ~/python

wget http://www.python.org/ftp/python/2.7.x/Python-2.7.x.tgz

tar zxfv Python-2.7.x.tgz

find ~/python -type d | xargs chmod 0755

cd Python-2.7.x

2. Install Python

./configure --prefix=$HOME/python

make

make install

3. Modify the Environment

    vi ~/.bashrc

Add this line at the end of the file: 

export PATH=$HOME/python/Python-2.7.x/:$PATH

source ~/.bashrc

4. Add Apache Handlers on User's CPanel control panel

cgi-scripts .py

5. Testing

vi tes.py
#!/home/username/python/Python-2.7.x/bin/python
import cgi
import cgitb
print "Content-type: text/html\n\n"
cgitb.enable()
print "Hello, world!\n"
print "<p>"
import sys
print "Python version is ",sys.version

note: /home/username is user home directory on CPanel

6. Check the result

http://xxx.somedomain.com/tes.py
"
Hello, world!
Python version is 2.7.8 (default, Jul 9 2014, 11:18:17) [GCC 4.4.7 20120313 (Red Hat 4.4.7-4)]
"

7. Install PIP

wget https://bootstrap.pypa.io/get-pip.py

python get-pip.py

8. Install Numpy, Scipy, Matplotlib

pip install numpy

pip install scipy

pip install matplotlib

One last thing to remember, do not forget to change file permission to 755 to make it executable. This should be enough :-)

[Update July/14/2014]

Install PYRAMID
pip install --install-option="--prefix=/home/username/python" pyramid

--> Installation OK, however, this line:
server = make_server('0.0.0.0', 80, app)

raised an error --> socket.error: [Errno 13] Permission denied

which is understandable. Pyramid installation is not a success yet.

My LM1875 Evolution

I've been quite some time away from the DIY world actually, and even decided to give up the idea of building my own sound system. Further, I bought a 2.1 system, an Edifier C3 to be precise, and decided to stop my DIY hobby. Then I started collecting FLAC files from the Internet, listening to some audiophile musics through this nice Edifier C3 which is not bad at all. But the same old nostalgic feeling came across and I started to question my listening experience with Edifier. Later, I started to check my account at diyaudio.com and renew my password since I have long forgotten it. The rest is, you've probably guessed that

On December 29, 2013 the schematic was updated as follows:

A fellow DIYer reminded me to route the blocked DC offset to ground through 22 k resistor from entering IN(+) of the amplifier. Another fellow recommends higher value (470 uF) of NFB-shunt capacitor. A zobel of 10 ohm resistor in series with 100 nF capacitor is installed before the output capacitor (4700 uF) near the speaker terminals. Now this amp plays Deep Purple's Pictures of Home, Duran Duran's Rio and Avenged Sevenfold's This Means War very nice. Treble and bass are just enough. :-D

Node Ordering (1)

Random matrix of 20 x 20

Maximum number of branches per node is 4

Random matrix of 200 x 200

Maximum number of branches per node is 200

Random matrix of 1000 x 1000

Maximum number of branches per node is 1000