RIP Rik Mayall

What’s wrong with this picture?

Something fishy going on in twitterland methinks. When I first visited @rikmayall on twitter there was a single post dated 13/04/2010. When I went back to show a friend things had changed…

Rik Mayall  Rik Mayall





Fishy.

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Fang - Mike Seyfang

TriBeardLesBones

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Web pages slow to load OSX 10.6 Snow Leopard after change from Billion to Fritzbox ADSL2+ router

Browsers (safari and chrome) on old unpatched OSX 10.6 snow leopard are slow to begin loading some pages after changing from Billion to Fritzbox ADSL2+ router on my Internode connection.

Patching to the 10.6.8 combined update for OSX did the trick!

My guess is that it is IPv6 related. See below for a list of symptoms / things I tried that did *not* work:

  • DNS / Name resolution in general: access to sites like http://www.google.com (ie search) or code.google.com worked but sat on ‘contacting google.com’ for ages. Paste an IP address (obtained from ping) and access was immediate.
  • NSLookup from terminal was always fast – even for sites with multiple IP addresses like http://www.google.com and code.google.com
  • Changing TCP/IP advanced settings on OSX system preferences (manual IP addresses, hard coded DNS servers, excluding my router’s IP address from DNS server) made no difference. Neither did messing with proxy settings.
  • Changing from ‘ISP default’ to known good DNS servers on fritzbox admin console made no difference.
  • NameBench ran, took a long time and did not report anything useful
  • Changing back to Billion router made problems go away immediately, Switch back to fritzbox and they return.
  • Symptoms first appeared when booting of old external HDD image of OSX Snow Leopard that had not been patched for years. Rebooting to usual patched version was fine. First I suspected DHCP / IP Addressing issues.
  • After finding and applying the combined 10.6.8 OSX Snow Leopard patch the problem immediately went away.
  • I suspect that I could have worked around the issue by fiddling with IPv6 settings for Fritzbox / OSX but did not have time to do that.

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Fang - Mike Seyfang

TriBeardLesBones

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OSX Force empty Trash [terminal rm -R does the trick]

Could not empty trash on my Mac OSX 10.6.8 Snow Leopard. Kept getting the error:

 The operation can’t be completed because an unexpected error occurred (error code -8003).

No matter which keys I hit while empty trash (shift, ctl, option, cmd).

This MacWorld article contained the clue that helped me.

DIY Terminal tricks

However, all those utilities merely send OS X commands that you can issue yourself in Terminal. To do so, first open Terminal (in /Applications/Utilities). Typecd ~/.Trash and press Return. Then, type sudo rm -R followed by a space (don’t leave out the space character—it’s essential). Don’t press Return yet.

Next, click the Trash icon in your Dock to open a window displaying the contents of the Trash. Select everything in that window and drag it into the Terminal window; this action adds the paths of all those files and folders to the rm(remove) command. Now, press Return and enter your administrator password when prompted. In a moment or two (depending on how much was in your Trash), the Trash icon should return to its empty state.

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Fang - Mike Seyfang

TriBeardLesBones

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Damn you FaceBook for stealing my attention

Haven’t blogged (or tweeted) in a while.

Seems FaceBook has stolen my attention and that of those I care about.

This time last year we were in Paris as part of our fantastic voyage to celebrate Mandy’s 50th. Thought I look through my old posts and facebook timeline to see what I was doing on this day one year ago. I found a few blog posts but scrolling back thru my own facebook timeline was a better experience. I wonder when they will start charging for that?

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Fang - Mike Seyfang

TriBeardLesBones

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(Opto) Photo Interrupter – pushing the limits

The z1670 photo interrupter from altronics ships with a 3mm gap through which an obstacle must pass to trigger a voltage drop that can be detected as  digital state change by something like an arduino. What if you want a wider gap? How far apart can the IR LED and the Detector be?

Electronics

About 13mm seems to be the sweet-spot (indoors on a mild day).

While I was able to measure a voltage drop at distances up to about 20mm (which could be detected as an Analog input to my Arduino project), it seems that things degrade pretty quickly after about 13mm. Using the resistor setup I describe here, 13mm gives an input reading of <100 as an analog input with gap open, and jumps to 1023 when closed – ideal for digital LOW/HIGH state change with good margin for error in differing conditions.

Here is the data:

Untitled

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Fang - Mike Seyfang

TriBeardLesBones

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Frankensteining old Internode router for WiFi on Telstra BigPond

Wrong.

In the end I had to set up two separate IP networks and get the Billion BiPAC 7404VGP to forward packets by setting up an ‘IP Alias‘. Set as DHCP relay agent.

Not as elegant as a single IP network but simple enough once you figure out the design and the funky terminology in the web based user interfaces for each device. However, the path to get there was anything but simple thanks to Telstra device locking, sloppy user interface design and firmware by Billion and an annoyance of half-arsed forum posts. With a bit of luck this blog post will save somebody (probably me) some pain when they try to re-use some old gear to get people on the internet.

  • Telstra have locked the thomson speedtouch 536 configuration to suit their BigPond network. My plan was to change the LAN IP address range from 10.0.0.x to 192.168.1.x to match the factory defaults of the Billion. Could have proceeded down the ‘update and unlock’ path but life is too short. The IP address for this router is 10.0.0.138 – whodathunk!
  • Couldn’t set  Billion LAN IP address range to 10.0.0.x The bipac7404vgp gave error “webserver:Invalid value 10″ every time I tried to set it’s LAN IP address to an unused address in this range.
  • Didn’t notice anything in the Billion configuraion User Interface that looked like it would forward packets from a 10.0.0.x network to a 192.168.1.x network until after I upgraded it to the latest firmware. (Doesn’t mean it wasn’t there, I just didn’t find it – and I cant be arsed going back old versions and looking).
  • Updating the bipac7404vgp firmware from a Mac running OSX snowleopard 10.6.8 was a pain in the arse.
    • The .zip files on the billion support downloads site contain another compressed ‘.afw’ configuration file which is what the firmware update interface is looking for
    • Many OSX methods for unzipping the .zip file give varying results.
    • Firmware Upload Failed
      Failed to write to file system.
      Failed to update FLASH chips.
      This may be due to a corrupt FLASH filing system.
      You can attempt to repair this by saving configuration.
      error
    • Use terminal in OSX to unzip the .zip file is the most reliable
    • Restart router using Factory defaults *BEFORE* attempting firmware upgrade
    • Still no joy
    • Out of desperation I grabbed the 7404VGPM firmware (even though every physical marking or configuration page said mine was a 7404VGP), unzipped the .zip using OSX terminal, restarted from factory defaults – this time it worked.
  • After the firmware update, I still couldn’t set the Billion’s IP Address to 10.0.0.x range but I did notice ‘IP Alias’ in the configuration pages for the first time.
  • Set up an IP Alias of 10.0.0.254 for the Billion with subnet mask of 255.0.0.0. Remember the SpeedTouch router address is locked at 10.0.0.138 and it’s DHCP server dishes out client addresses starting at 10.0.0.1.
  • Turn off DHCP server of Billion (set as DHCP relay agent).
  • Took the Billion around to the in-laws, used a spare Cat5 10baseT ethernet cable to connect from LAN port 1 on the Billion to the unused Ethernet Port on the Thomson Speedtouch (checked for the green link status light on each port – you guessed it, the first cable I tried failed!).

After a bit of fiddling around I managed to get an iPhone, iPad and my Android phone to connect to the WiFi from the billion, get an IP Address in the 10.0.0.1-20 range (shows up in the speedtouch status page at 10.0.0.138) and surf the world wide inter-tubes courtesy of a locked BigPond rooter. Yay!

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Fang - Mike Seyfang

TriBeardLesBones

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LoLa Prototype v1.1 = SUCCESS

It Lives! A broomstick driven, photo interruptor sensor enabled pendulum that uses MIDI to make a sound for each half swing.

As part of my research for the Institute of BackYard Studies , I am prototyping various components for a Lightly Oscillating Linguistic Organ (LoLa) – a musical instrument that harnesses the sinusoidal beauty of the pendulum wave.

After much fecking around with magnetic reed switches, analog light sensors, mercury switches, mp3 players and android phones I have finally iterated toward a reliable setup.

  • A $2 Opto (or Photo) Interrupter sensor. For two bucks you get a little plastic gizmo that has an IR LED and detector separated by a 3mm gap. A couple of resistors and some fancy PCB wiring and you can make a digital input for the Arduino.
  • Arduino Sketch that detects a change of state on said digital input and sends a MIDI note command via the serial output.
  • A very simple 3 wire connection to a DIN 5 Connector for MIDI Output (Not quite MIDI standards compliant – need an opto isolator circuit for that).
  • MIDI to USB input to an old mac mini that was lying around (PowerPC – OSX 10.5).
  • SimpleSynth midi synth running on OSX 10.5.
  • MIDI Monitor for OSX to debug things.
  • Headphone output from mac mini to an old ghetto blaster in my shed to make noise louder.
  • A work of art! (in the making).

Here is what I learnt:

  • MIDI can be deceptively simple and frustrating
  • On arduino DUE when using the +5V MIDI DIN 5 circuit as per all the instructions out there just got jibberish. By pure chance I tried +3.3V and it works like a charm.
  • I probably spent as much time getting the sketch to reliably start with the MIDI sound I wanted (church bell) as I did on the rest of the MIDI work, including cabling.
  • I probably should have started with a photo interruptor already wired up as an Arduino sensor rather than go down the rabbit hole of circuit diagrams, datasheets and the futility of resistance!

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Fang - Mike Seyfang

TriBeardLesBones

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