Darryl Smith @ Radioactive Networks

Tuesday, August 03, 2010

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Monday, December 07, 2009

I got a new video card for my Dell GX280 computer today. I ended up getting an Asus EN9400GT video card. This is a half height design which would fit into the case. With the half height adapter it did fit but the HDMI was unusable. This is fine as I had a DVI to HDMI adapter.

Unfortunately, the device did like my TV, in terms of sound. The sound connection was via a Line Input on my TV, and the new video card had an audio channel with nothing on it. So, I needed to hack the audio on the card. The input on the video card was S/PDIF but my motherboard did not have a suitable output. Thankfully I did have a spare RCA Analogue to SPDIF/Optical. So I hacked it. I powered the converter with 5V from the power supply, and added an RCA connector for the cable to the video card. This worked well.

A minor amount of metal work was needed in the area of the HDD mount to get the case to shut, but apart from that the card looks like it works well

Sunday, December 06, 2009

Interfacing a Video Intercom as a Door Bell

This might seem strange, but I have found it hard to buy a decent door bell pushbutton. They all seem just wrong. And I don't feel like spending $40 on a pushbutton that looks horrible either. Anyway, I was looking through the WES catalog to buy some supplies, and found some Video Door Intercoms. The camera unit was $40 for B&W, or $50 for colour. And they included a pushbutton. WOW. This one was a LOOK-C unit.

This did not include the base unit, but who cares. Debugging the four wire interface I worked out how they work. First, the 12V is only active when the unit is fully active. The video signal is therefore only active when 12V is supplied. And the ground is simple. The audio does the rest. When there is 12V or so on the audio line, the internal relay is activated causing the door strike (if attached) to open. And if the button is pressed, the voltage on the audio line goes to ground. The audio line normally sits at 5V.

Audio signals going both ways sit on the single audio line, meaning that there must be a hybrid in the camera unit allowing for hands free.

To interface to my alarm, to use the Alarm as a door bell, I purchased the KC5377 Voltage Switch Relay Kit from Jaycar. This was under $30. To simulate the 5V, I took the 8V from the regulator and connected this to the input of the switch via a 100 ohm resistor. Then I connected the input to ground via a 220 ohm resistor. This gave a bit over 5V at the input. The I then tuned the relay settings so that it would detect the pushbutton.

This seems to have worked well. I have yet to install it, but I am sure it will work

Tuesday, October 27, 2009

ESXi 4 and USB issues

I had some USB issues when installing VMWare ESXi 4 on some non-VMWare approved hardware today. I was installing onto an ICH10 motherboard. In fact, by USB troubles, I mean I had major issues. I think I have solved them, but I am not sure of the exact solution.

Anyway, my install would die when trying to load one of the USB drivers. It would just sit there and sit there. Using a PS/2 keyboard would almost work, but would reach a screen that asked for me to press enter, and that did not work. I also had the machine hang on IDE.

The solution is simple. First, turn off the legacy IDE. I had SATA, and so I did not need IDE. I don't know if this did anything, but it did not hurt. I also turned on VT in the bios. This was probably important too. The CPU I was using was a Core 2 Duo... The E-7500 running just under 3 GHz.

The solution to the lock ups? Simple. Remove the USB keyboard and mouse as soon as possible at the beginning of the Yellow and Black screen. Then just before it ends you need to put the keyboard back in. Actually, you can do this once it gets to about 2/3rds of the way through the process.

What this does is removes the USB device so it is not detected incorrectly by the VMWare software. Then, once we have gone past that step, the Plug and Play will detect the keyboard as a keyboard and things will be fine. I don't know if you need to remove the USB on reboot, but the solution to that is to log in via SSH to the VMWare and edit a conf file in /etc

Tuesday, July 14, 2009

Python SoapLib with VB.NET and C#

This is a rare post. It says how to do something, and it is something that I have spent a LOT of time investigating. It is not complete thanks to one or two issues, but it is close.

Basically I wanted to write a service in Python and consume it in VB.NET. That should be easy. Well, it is, if you want to write your own Web Service code under .NET. I am lazy and do not like that idea. So you need to generate a WSDL from what I can work out. And this code does that for VB.NET and C#, at least in Visual Studio 2005. There is an issue though. Data types are not being sent correctly. I think this is an issue with SoapLib, but I cannot be sure. The GIT repository does not have any patches either. So this is CUTTING EDGE!

Sorry about the lack of indent. I am sure you can work it out!


#!/usr/bin/python
import web
from soaplib.wsgi_soap import SimpleWSGISoapApp
from soaplib.service import soapmethod
from soaplib.serializers import primitive as soap_types
from soaplib.serializers.primitive import String

urls = ("/hello", "HelloService",
"/hello.wsdl", "HelloService",
)
render = web.template.Template("$def with (var)\n$:var")


class SoapService(SimpleWSGISoapApp):
"""Class for webservice """

#__tns__ = 'http://test.com'

# @soapmethod(soap_types.String,_returns=soap_types.String)
@soapmethod(String,_returns=String)
def hello(self,message):
""" Method for webservice"""
return "Hello world "+message


class HelloService(SoapService):
"""Class for web.py """
def start_response(self,status, headers):
web.ctx.status = status
for header, value in headers:
web.header(header, value)


def GET(self):
response = super(SimpleWSGISoapApp, self).__call__(web.ctx.environ, self.start_response)
return render("\n".join(response))


def POST(self):
response = super(SimpleWSGISoapApp, self).__call__(web.ctx.environ, self.start_response)
return render("\n".join(response))

app=web.application(urls, globals())

if __name__ == "__main__":
app.run()

Monday, June 08, 2009

Hints Replacing a Gyprock/Plasteboard Ceiling

Removing the old ceiling is easy. Hammer or pry bar or whatever. It will generally be screwed or nailed as well as glued. Remove the nails or screws as you find them. Don't worry about getting dried glue off any wood work. Not worth the hassle.

Work out what size cornice is installed, or more importantly what you want to replace. When you buy the cornice, get a cutting jig. They are cheap and commonly made from plastic.

Once you have removed the plasterboard, you will need to measure up for installing the new board. Since the cornice is going to cover the edge of the plasterboard you should cut the board a bit small. If you leave it to go right to the edge you will run into issues.

If you can, buy or rent a stand to hold the plasterboard to the ceiling. Otherwise make sure you have at least two people. A third comes in rather handy.

Work out how you are going to secure the plasterboard to the wood. Commonly these days self tapping screws are used in association with builders adhesive. You can get a good idea as to how much adhesive is needed from looking at what was used before. Ideally install the adhesive to the top of the plasterboard, but you can install it direct to the woodwork. We found it was better to install it to the woodwork with a paint scraper.

If you can, install a series of screws in the wall just below the ceiling height along the long side. Leave the screws so they are sticking out. These can then be used to lean the plasterboard on during install.

With the plasterboard held in place, install enough screws into the plasterboard to hold it flat and also hold it in place until the glue dries. Eventually the screws will need to be removed for screwed in so that they are below the surface. Either ways the holes will need to be filled.

When placing two boards next to each other, make sure that they have a slight gap as this will make it more likely that both boards will line up. Apply about 4" of filler along the entire seam. Then get some 2" plasterboard paper and put it in a bucket of water. Then apply it to the seam over the filler. Then use a scraper to remove any air bubbles. Then apply filler over the entire length and allow to dry. Once dry, sand slightly and apply another layer of filler.

The cornices can be a pain. There are a few tricks. First, apply screws to the wall just below the height of the cornice. These will be used to rest the cornice on whilst securing it. Cut the cornice to length. I have found generally I need to cut it about 1/2" long. Not sure why. It is then the right length when I install it.

Apply adhesive to the back of the cornice, but only when you are sure it is going to fit. Apply more to the top rather than the side as any excess will most likely be hidden.

It is important to install cornice so that it is touching already installed pieces if possible. This will minimise the issues with installing a piece of cornice that needs to fit next to two previously installed pieces. But you will need to install one piece like this in most cases. In this case, measure and cut the cornice as before, but then cut it in half. The join will need to be fixed, but this should be easy. If you are concerned, have this join so it will normally be behind a door.

Do not use extra hard filler unless you want to have problems with sanding.

Buy a special plasterboard sander. They are worth the little that they cost.

Thursday, December 18, 2008

Huawei, Optus and Maybe Telstra

The National Broadband Network tenders are all in. And Telstra is out. But someone has told that Huawei is linked to the Chinese Military. Strange Story. The opposition is really pushing the issue. But I am just wondering why. And where the story came from.

I am just guessing here, but could it be Telstra? The Huawei equipment is used by Telstra for their Next-G for some customers wanting broadband. But who would win if Optus drops out of the NBN? Would that be Telstra?