Monthly Archives: February 2009

@smiffytech – The Twitter and I

Important Note

As of 15 August, 2009, my Twitter identity changed from @smiffytech to @smiffy. The @smiffytech account still exsists, but with a message referring to the new one. Followers/following not affected.

Preamble

Until fairly recently, my only encounters with online social networking were with the professional networking site, LinkedIn. I have to confess that my impression of the other social networking utilities out there was “kids’ stuff”, “silly” and the like. Now that I have delved into these utilities, I have gained considerable respect for them – in concept if not in execution.

There are two main reasons for me looking into and taking up with various online social networking utilities. These are 1) my clients use them and 2) they are web applications; as a web applications developer, I need to keep current with applications being used at large.

I have decided to take up regular Twitter usage because, even in the short space of time that I have been using it, I have made some valuable and interesting contacts. Despite its limitations, Twitter is a valuable tool and, from a business perspective, only a fool would ignore it.

Twitter

The history and actuality of Twitter are a matter of public record so I feel no desperate need to regurgitate a load of facts in this article.

These are what I consider to be the key points of Twitter:

  • Posts are limited to 140 characters. I know the reasons for this, I don’t like them and I don’t like the restriction. But that’s what Twitter is, I don’t see it changing so one must put up with it.
  • Twitter has a publicly available API so anyone can develop their own add-on, value-adding or whatever software. I consider this to be a very important feature.
  • Threading is limited; whilst one can reply to a “tweet”, the reply appears to be linked only to the parent, not to an entire thread.

Usability/Accessibility

Accessible Twitter icon

Twitter has in common with every social networking utility I have seen so far – the web interface is crap. I’m not knocking the developers here specifically – it still seems that only a minority of those developing for the web have even the faintest clue when it comes to accessibility or web standards. However, by offering an API, Twitter gains itself Brownie Points because this allows others to develop better, more accessible interfaces. Step forward Dennis Lembrée, the creator of Accessible Twitter. (Dennis is @AccessibleTwitr on Twitter.) Whilst this service is only in alpha at the time of writing, the work done so far has been truly excellent.

Followers and Following

Whilst one can sample the random noise that is the Twitter live feed, to get any sense out of this vast flow of information, one needs to “follow” specific users. For me, the first people that I follow are those in my own “tribe” – those that I know in real life – friends, colleagues, associates, etcetera. Others that I follow are those who follow me; I choose these based on a certain set of criteria – more of that later.

So, do I just follow everyone that follows me? Absolutely not! Whilst Twitter is important to me as a network builder, I don’t want to spend excessive time looking at it or suffering from information overload.

My “following the followers” are:

  • If a new follower has too few posts that are of interest to me, I don’t follow them.
  • If a new follower has posts of moderate interest but is posting a vast volume, I don’t follow them. Until such time as I have written my own Twitter-reading code to help me sort through posts, I need to keep the incoming volume down to what I can easily handle manually. Twitter may get me new business, but looking at it doesn’t get my work done.
  • If a new follower is following many, has few followers, has no posts and not completed their profile, I will block them straight away.
  • If a new follower is following many, has few followers, has no posts, has completed their profile, but still has no posts after 24 hours, I will block them unless I have good reason to believe that they are genuine users only just getting started.
  • If a new follower has only made spammy posts, I block them straight away.

It’s a Game!

Er, no, I don’t agree. It seems that there are those that use Twitter as a means of self-gratification, measuring their “success” by their number of followers. I believe that any form of success in social networks is the number of meaningful relationships that one establishes – quality being significant rather than quantity.

But each to their own. I want to build professional networks, others want an ego-trip. Twitter appears to be able to provide both.

Further Reading

 

Cheers all!

Smiffy, aka @smiffy

TinyURL for this post: http://tinyurl.com/clar7f

Max Design CSS and Accessibility workshop series – May 2009

I have received a mailing from Russ Weakley (Twitter: @russmaxdesign) advising of the Max Design CSS and Accessibility workshop series being run May 2009:

Day 1: A practical guide to preparing WCAG 2 compliant websites

Roger Hudson

An all new accessibility workshop that focuses on providing practical advice to help developers and organisations comply with the Web Content Accessibility Guidelines, Version 2.0.

During the day, you will learn the importance of web accessibility, how to overcome common accessibility problems, how to reduce the risk of a discrimination complaint, and the techniques for complying with essential WCAG2 Success Criteria.

Day 2: Mastering CSS and XHTML – building elegant websites

Russ Weakley

Over a full day you will build a detailed website layouts from the ground up – starting with flat graphic mockups; and ending with clean markup and elegant styled pages using XHTML/CSS.

The course will cover styling forms, writing efficient CSS, use of sprites, sliding doors, dealing with browser bugs, creating print CSS and styling for different screen sizes.

Dates

Sydney – Monday 18 May and Tuesday 19 May Canberra – Thursday 21 May and Friday 22 May Melbourne – Monday 25 May and Tuesday 26 May Brisbane – Thursday 28 May and Friday 29 May

More information: http://maxdesign.com.au/workshop2009/

Ada Lovelace Day – Women in Technology Whom I Admire

It starts thus:

“I will publish a blog post on Tuesday 24th March about a woman in technology whom I admire but only if 1,000 other people will do the same.”

this being from coffee.geek.nz

I am fully aware that the technical sector – whether it be IT, engineering or medicine (which I consider technical) – has always been very much a “boys’ club” and am embarassed to be a part of such a misogynistic industry.

Whilst I admire what Ada did (writing programmes without a computer is no mean feat), I would like on this occasion to recognise 3 women of my own acquaintance. They may not be Big Names, but they are just some of those that I can name whom I consider worthy of respect:

  • Leah MACLEAN. Leah is a technology veteran, having worked for Telstra, Australia’s national telco. Leah now provides technology services and understanding to her clientelle (primarily women in small business) as Working Solo.
  • Liddy NEVILE. Liddy Nevile is an Adjunct Associate Professor in the Advanced Computing Research Centre at La Trobe University. I know Liddy as the drive behind OzeWAI web accessibility conference and a member of the Dublin Core Metadata Initiative.
  • Lynne POPE – head honcho of the Mambo CMS project and another technology veteran. A serious Mover and Shaker in Open Source software development.

There are others that I could mention of my personal acquaintance and of no less merit, all just going about their jobs despite the frequent discrimnation that they face. (They not only have to be good at their jobs but also able to survive being Eaten By Trolls.)

Please, let’s just shed the obnoxious attitudes that make the technical world a hostile one for women and rid ourselves of any stupid ideas of women being less able in this – or any other – field.

And yes, I know that this article is over a month early but, by writing it now, at least I know that it will get written.

Shortened URI for this page for Twitter users and the like: http://tinyurl.com/bqmjzk

Here is a list of Ada Lovelace Day posts from others: http://ada.pint.org.uk/

The Solstice Clock – Part 3

schematic of solstice clock prototype
Solstice Clock Schematic

Solstice Clock Circuit Design

In part 1 and part 2 of this series, I started to describe my concept of a Solstice Clock and some of the design parameters. This post is just a brief note to present the circuit schematic for the clock motor driver and the corresponding circuit board layout.

Minor Changes

I have made a minor change to the circuit as described in the previous article. The circuit now includes an 8-way DIP switch rather than a 4-way one. The reason for this is to provide a means by which the length of the pulses driving the clock motor may be controlled. Too short a pulse and the clock may not tick or – even worse – tick intermittently. Too long a pulse and excessive power is consumed. Whilst I do not see the solenoid or microcontroller getting burned out, a reduction in battery life would occur.

In a production environment where only one type of clock mechanism is being used, it is possible to find a pulse length that works with all members of a batch of mechanisms and set the pulse length in the firmware. For prototypes however, especially when different mechanisms may be used, the ability to change the pulse length without re-programming would appear to be most appropriate.

Board Layout

Solstice Clock Board Layout

The image of the board layout presented here is – theoretically – 1:1 scale. It is on my computer but I have no idea how other web browsers may mangle it. For those in doubt, it has about the same footprint as a box of regular safety matches. Before you say "whoopee, isn't it small?" I would advise that this is just the controller board. Somewhere in the back of the clock we need to fit in a pair of AA cells to power the thing. These may be either in two single holders (might make it easier to fit in) or together in a side-by-side holder.

The Solstice Clock – Part 2

Preamble

In Part 1 of this series, I outlined my concept of a Solstice Clock. Since writing the original article, I have modified a regular quartz clock and have estimated the requirements to drive it.

Simplification

My original drive circuit was rather complex – excessively so. Having now reconsidered the requirements (for instance, removing the facility to set the time via a serial data connection) and calculated the drive requirements of the clock solenoid, I have found that a minimal implementation of a Solstice Clock could consist of no more than a microcontroller, timing components a couple of BAT54S dual diodes (protection for the 2 port pins connected to the solenoid) and that's about it.

This more minimal system would use less power (runs on a pair of AA cells – the original would have required 4 or 5) and also fit into far less space than the original. The latter consideration could be important if there is little space in the back of the clock for modifications.

Choosing a Chip

Whilst the very minimal version could be implemented with an Atmel ATTiny45 – making for a very small circuit board – I have decided to make my prototype with a little more flexibility which requires more than the 8 pins of the ATTiny45 and have thus selected the ATTiny2313V. The 'V' is significant – this lower-powered version of the device can operate right down to 1.8V with a clock frequency of less than 4MHz or 2.7V with clock frequencies all the way up to 10MHz.

After playing around with a spreadsheet, I checked some crystal values to see what gives the most accurate results. Actually, it wasn't quite that way – I first looked on eBay for cheap job-lots of crystals in the 3Mhz to <5Mhz range and then ran those through the spreadsheet to find the ones most suitable. I now have batches of 4.9152MHz and 3.579545MHz crystals to play with. There is a trade-off between the time resolution that I can obtain and power consumption; the higher the clock frequency, the better the resolution, but the higher the power drain.

More than just the Tropical Year

My original plan, when I was thinking of controlling the clock through a serial interface, was to be able to vary the 'tick' rate to allow for differing year lengths. Whilst I am now using a mean Tropical Year (so a fixed length), I realised that it would take little effort to provide other mean periods that the clock could operate on. The final list is this:

  • 1 Tropical Year
  • 1 Synodic (Lunar) Month
  • 12 Synodic Months
  • 13 Synodic Months

These 4 periods would be selectable by two positions of a 4-bit DIP switch. This leaves me with 1 switch to control stop/run and another switch reserved for future use.

Setting Up

I have discovered – somewhat to my annoyance – that most quartz clocks provide a means of setting the hour and minute hands, but not one for setting the position of the second hand. As this hand is representing far more substantial periods of time in my slowed-down clock, I have decided to provide the means of setting this hand through the electronics. The stop/run switch will be set to stop, then a push-button held down until the second hand is at the appropriate position. The hour and minute hands would then be adjusted by the regular twiddler on the back and the stop/run switch set to run when ready.

Moving On

In the next article of this series are presented the circuit schematic and board layout of the Solstice Clock prototype.