The video is great as the setting and content (making use of a famous mind and quote) which is only made apparent at the end keep the viewer engaged for the clip length: You need the subject, content and delivery method to keep the viewer engaged; its a great example; and on a side note also reminds us to think about what we are being told and to not take it for granted as being correct!

Thanks for sharing the video.

Michael
http://www.southshorediet.com/

I am also a great fan of Einstein. I read his biography again last year and am amazed at his intellectual honesty and his ability to see through the false reasoning we can too easily settle for as truth. As the father of quantum mechanics for which he got his Nobel Prize awarded in 1922 for the paper he wrote in 1905 looking at the photoelectric effect where he showed that a statistical analysis of Wien’s formula looking at the wavelength distribution of the heat radiation could account for the effect where electron emmission from an illuminated metal surface could be explained if the light were considered to be in quanta or parcels or particles. Although he later struggled with some of the conclusions that quantum mechanics woudl come to he also did the math that eventually proved them to be true and did not shrink from fixing their formulas even though the results were disturbing to him. A truly remarkable and laudable individual.

In the field of electronics and embedded software development which is where my company operates we issues to face and resolve although they are not as fundamentla as the ones Einstein faced.

If you want to solve a design problem, it is important to know what assumptions you are making and to test that they are correct. Unchallenged assumptions can be one of the biggest sources of project failures and managing and eliminating risks early in a project is a strategy we use to ensure we consitently deliver projects on time and on budget with all the required functions and features.

The other area where this same issue arises is fault diagnosis and debugging. Again it is assumptions and poorly thought through symptom analysis that can lead to a lot of frustration and wasted effort. I recently repaired a corrosion protection data logger that had developed a fault in the field. It didn’t communicate back via its 802.15.4 RF wireless telemetry link and when I opened it up and checked inside it did not seem to start up even with new batteries. The power supply voltages were all correct so it wasn’t that.

First tip – check the power supply before looking at anything else. Electronics rarely works correctly with a faulty power supply and the power supply is one of the most highly stressed electronics components making it more likely to fail.

Second tip – check the wiring.

This product only has 2 wires so checking the wiring was easy. But this is normally one of the first things to also check; that the leads, wires and connectors are all in place and correctly mated. I once reapaired a personal computer that appeared to have a driver problem with the printer when in fact it turned out that the cable from the motherboard to the rear panel connector had come loose. I wasted an hour trying to fix a software error when it was really a hardware problem. Plug in the cable and all is fine again.

But in the case of the data logger, the wiring was fine. This is good cost reduction strategy since wires, connectors and assembly labour are often way more expensive than the extra printed circuit board size needed to eliminate them all. And it also removes a potential fault source so it is a double winner as a product development strategy.

Next I tried connecting to the microcontroller using the In System Programming (ISP) connection. No response. The power supply is OK but the microcontroller doesn’t respond. They are usually very reliable. This particluar part was an Atmel AVR ATmega644P with dual UARTs and lots of FLASH, RAM and even on board EEPROM. I did a series of other measurements and concluded that it looked like a fault with the microcontroller. This is very rare for an Atmel part and the first time I have seen it in this processor.

So I desoldered the microcontroller using a hot air Surface Mount rework station and replaced it. I then went to program the new microncontroller and it programemd fine. The In System Programmer connected to the part, programmed the embedded code into it and set all the fuse settings so it would operate in bootloader mode with code protection and an external crystal oscillator.

I removed the ISP and restarted the Data Logger. No response. Reconnected the ISP. No response. Another data point for the debugging. But a frustrating one since I’m now sure that it isn’t the processor and Atmel has an intact reputation again.

So what changed when I programmed it?

There is only one thing that it can now be. The external crystal osciallator. The Atmel AVR parts come from the factory operating off an internal RC oscillator but can be set to use an external crystal oscillator. They will program up fine until you exit programming mode at which point they try and do what you told them to do, and use the external crystal oscillator. If the osciallator is faulty, they can’t operate. So I replaced the crystal and all is fine again.

So could I have done this differently? The answer is obviously yes but I made an asssumption. One of Murphy’s Laws of Technology states that “Logic is a systematic method of coming to the wrong conclusion with confidence”. You can see the rest of them here http://www.murphys-laws.com/murphy/murphy-technology.html

If the microcontroller had of indeed been at fault, changing the crystal woud have achieved nothing. But changing the crystal is an order of magnitude easier than changing the microcontroller. And I was familiar with this design since we designed it and recently got 2 National Innovation Awards for the work we did on it. If you are interested you can check that out at http://www.successful.com.au/blog/2009/09/18/edn-innovation-awards-2009-2-trophies/ . After discussions with our client, Borgtech, it is likely this particular unit was dropped from a great height. If I had known that then I might have decided to look at the crystal first since they can shatter if subject to high shock loads and you have to buy special types for very high shock environments.

So the moral for me is: “all things being equal, check the easiest thing first!”

I’m sure you can identify equivalent scenarios in your own area of interest.

Thanks again Marc for such a great reminder of Einstein’s brilliance and honesty.

Ray Keefe
http://www.successful.com.au

Thanks for sharing

Michael

http://www.AustralianBullionCompany.com.au

The amusing part is that the zero point is arbitrarily chosen. It is generally considered that Jesus was born somewhere between 4 and 6 BC (which stands for Before Christ) so he was ahead of his time. But only because the first official attempt to backtrack to the correct year didn’t have good enough data or methods and so the baseline was set in the wrong place. If they had got it right, the moment we are looking at in this blog post would have been before the Beijing Olympics.

The profound part is that how we label things changes what they mean to us. And that changes how we respond to them.

So 0 degrees Celsius is the freezing point of water. But we have determined that -273 degrees Celsius is the real baseline for how cold things can go. This is also known as 0 degrees Kelvin and is named after Lord Kelvin. So from our perspective, a rise of 10 degrees is a significant change in the temperature but the universe sees this as a pretty minor adjustment.

Some electronics units of measurement:

- capacitance and the Farad named after Michael Faraday. Mostly we work with microfarads and nanofarads and picofarads which are 10^-6, 10^-9 and 10^-12 smaller than a Farad. So the baseline was set huge and we have been dividing down ever since.

- inductance and the Henry named after Joseph Henry. This isn’t as bad since we are generally working in millihenry and microhenry values when designing with electronic circuit elements. I’ll ignore parisitic effects.

- watts, volts and amperes (also called amps) work out pretty well as do Ohms (for resistance). These rarely get below the 10^-6 region and are often in whole units. Though we do a lot of low power electronics and these generally try to run in the microampere territory for operating current.

Now I thought about trying to post this at exactly 12:34:56 7/8/9 but then I realised that moment would come at a different time in each time zone. And the time zones even out what is really sliding time. So I’ll just do it now.

I also don’t know the relationship between the blog host’s time zone and mine though there are ways to work that out if I cared enough about it.

Better stick to designing electronics products for manufacture in Australia by Australian electronics manufactures.

Ray Keefe
http://www.successful.com.au

Thanks for pointing it out – I had not considered the day / date tomorrow – but will make sure I am looking at the clock about mid day!

Michael
http://www.southshorediet.com/

DC