CCS Hand held programmer.

My product uses a PIC12F675 and up until now I have been programming my devices either at production and/or for custom settings, using a Picstart Plus programmer.

All well and good if you are as ‘geeky’ as we are, but how about for field updates by someone who has no idea about microcontrollers etc.

This is where this ‘you beaut’ product from CCS Inc. comes in very handy. Your ’support’ team need only to know how to connect to the field device and this unit does the rest at the push of a button!.

I am very impressed with said unit and will update you on more features in a future post.

Around March this year I was approached by a partner company to re package a design I had done nearly 14 years ago for a new product to be launched this year. Back then I was still “cutting my teeth” on micro controller based products and hence the outcome was a conservative but (even if i say so myself!) yet relatively (all these caveats!) reliable product. (I base this on the fact that over this period, 12000 units were sold with less than 100 returned, not necessarily because of bad design but more oft than not, physical abuse).

Now fast forward to the 21st Century…ok, so the old product was simple and reliable and used a particular (now patented) sensor mechanism but, this sensing technology I decided, was not suitable for the new design.

Technology had moved on (though the old design is still selling well in its original form and respective market) and 14 years of experience in the field has taught me new tricks and techniques.

The product I am talking about is a touch sensor switch used to flush toilets (ok, its not a glamorous area to be involved with but hey, it pays the bills!). The original design was and still is, ground breaking in that it allowed touch sensing through a continuous sheet metal plate. The technique utilised was differential sound detection between sensors on the back of the sheet of metal. (For which we got and still maintain a patent for.)

The new product however, was not metal or ferrous based material and hence opened up new sensing techniques (or old ones revisited) to be considered.

About this time (Mar 2009), Microchip reincarnated (along with several other vendors such as Cypress Microsystems) capacitive sensing. Something I had read about and played with from time to time but was always scared off by some horror stories over the years.

So what did Microchip achieve in this new reincarnation?

Not much really, it was just the implementation of some smarter algorithms and in the case of the micro I eventually chose, a programmable current source coupled to a 10 bit ADC.

That was a the relatively easy part. Remember, my original sensor was stated as being a rather conservative design and generally the risk factor was low. It was a good “Brute force design”. I also had the luxury of plenty of space and volume to put all the parts in.

Not so with the new design!.

The new design was being driven by new management open to new ideas and potential sales. I was also in the situation where I needed this product as well as them. So I used the cost budget to the maximise and incorporated every feature I could think off in order to get the design job. Big mistake!

The spec was now not so simple and I was definitely “digging myself a hole”, because unbeknown to me, the timeline to launch was to get shorter in an exponential fashion very soon. (I should have known after so many years in this industry!!)

I thought… “hey! everyone is network enabling their products, so should we”. Then I thought another ‘killer feature’ would be sound for user feedback. (This, as I discovered later really gave me a lot of strife and some lessons to be re-learnt.)

Ok so as soon as the thought process goes that way, we are not talking simple…we are talking ’stacks’…communication stacks. Stacks take memory (my original design had only 512BYTES of OTP ROM!), lots of memory. Then there was the sound aspect, I thought, wow, how about some quality audio, not the usual iPod click but a smooth sound…I was sure heading for trouble again. The specs were mounting up but there was a particular apsect that was not keeping pace….

Throughout the years I have learnt that if you do not get your foundations to a design off to a good solid start, you are headed for BIG trouble. Yes, I am talking about the power supply.

My thought process was stupid in hindsight. This was a miserly power sucking processor, how could there be power supply problems. How wrong I was, but now I am definitely aware of how important a consideration this aspect of any embedded design is right from the word go.

With such tight time lines, you really need the ABC’s of a design secured from the word go and solid enough that you are not having to try some magic in firmware alleviate physical problems later on.

One problem I had was the fact that the power source was from a 24VAC plug pack. Even though I was only going to be drawing in the order or 50-100mA max, with the volume I had available, it was not going ot be an easy ride bringing this down to 3.3V efficiently.

I started with a linear regulator, but remember, I have 24VAC as the source half wave rectified, taking this up to around 36VDC (depending on load) peak!. Then I had to consider the inrush current, which with low ESR components pushed potential peak inrush voltages up to 50V plus!!!. most linear regulators cannot tolerate such high input differentials between input and output.

Even If I could find such a linear solution, the heat dissipation would have made the user interface feel uncomfortable. Not as in hot but instilling some doubt into whether the unit was stressed some how/

This then, basically threw the linear aspect out the window. (Perhaps a mixed discrete + asic could have done the job, but space was a limiting factor.)

The next option was to go for a buck converting solution. The issues here was volume. I did not have the headroom for relatively large inductors. Then by luck I came across a little ‘beauty’ from our friends at Linear Technology. The LTM8020 uModule. These ‘babies’ are fully integrated. Inductor, FET and all !!!. Their only downside is that they have a sort of BGA package making them rather hard (though not impossible) to hand prototype with. (I did manage to do this.)

Linear Technologies uModule

The LTM8020 is rated at up to 36VDC. so something had to be done to ensure this was not exceeded. A low impedance resistor after a couple of dual SOT23 diodes did the trick, bringing the input voltage into a safe area. (Semi’s are generally current tolerant but voltage starts to literally breakdown barriers even for an pft… of a mSec!)

I still had the issue of inrush, though this was a rare event as once the unit is commissioned it is powered for ‘life’ barring the odd power outage. This final factor let me get away with stressing some of the power supply input components to a measured extent, these namely being the input capacitors.

Something one would not even want to consider in this case is the use of tantalum capacitors, which are extremely voltage intolerant in a spectacular way!. Luckily there are ceramic capacitors and these are rated at up to 50V for 1210 packages and accordingly de-rated for higher peak voltages. The use of ceramics saved the day as they were ideal in this application in terms of voltage tolerance, ESR and form factor.

This feature is available across the PIC18 and PIC24 range and makes board layout a breeze. (Note, not all PIC18/24’s support this feature, see specific data sheet to see if the device has it)

Read more about this very powerful feature….

Link

Supercapacitor

Imagine a battery that you could charge instantaneously. What applications might that suggest to you?

How about the electronic equivalent of the centuries old flywheel? The basic principle of the flywheel is to store energy, for instance in a tramcar when it is braking, rather than waste energy as heat in a crude braking mechanism, a flywheel is employed to take the otherwise wasted energy (normally wasted as heat) and store it in a flywheel.

As beautiful as some of these mechanical systems are, they are bulky, need to be well balanced and maintained.

Enter the Super Capacitor!.

Those of you familiar with your average electrolytic capacitor know that they have a relatively low internal impedance meaning that you can store energy in them very quickly, far more quickly than readily available battery technology.

Their major drawback however in the past is very limited capacity. In the order of 10’s of thousands of micro farads.

Energy stored in a capacitor in joules is determined by the formula E = CV2/2 E is in Joules.

For example a 100,000uF capacitor rated at 50VDC can store 125 Joules.

I have in my hand here what looks like a D Cell, one of Maxwell’s BOOSTCAP®’s which has a capacitance of 350 FARADS!. That said, it is only rated at 2.5VDC but stores a whopping 1100 Joules. (Compare that with the above 100,000uF rated at 2.5VDC = ~ 300mJoules!)

Supercapacitors are making big inroads in the hybrid vehicle market and yes, the tramcar market. But just let your minf think oustide the square a little and think of all the lower power applications that could benefit from it.

Today there is a proliferation of RF based devices which all need their own battery supply. The batteries are great once charged, but they are far to slow to take advantage of say “energy harvesting” devices that rely on motion to generate energy.

I have plenty of ideas for the application of these devices, How about you?

Please join my LinkedIn group related to this subject.

Next time you are watching Wimbledon, NFL or the Cricket and they put on one of those fantastically clear slow motion replays spare a thought for the humble ADC (Analogue to Digital convertor).

These devices play an intrinsic part of modern day living.

You will find these in mobile phones, HDTV, telephones, radios, in fact almost anything that makes use of audio/visual media will be certainly using an ADC.

So what is an ADC?

adc image

Life is mostly analogue in nature things change from one state to another through a series of progressive levels. E.g. night turning into day. A night sky does not instantly turn to day light, it progressively gets lighter from night to day.

Sound is typically made up of analogue signals which change in frequency and amplitude.

Conditioning of analogues signals present all kinds of issues, most of all making repeatability of the signal very difficult.

Digital on the other hand has clearly defined states and although one analogue to digital conversion may not be Exactly the same, it is far easier to maintain accurate reproductions of the original source.

Going back 10-15 years or so, the only way slow motion could be achieved was by running through thousands of meters of film or magnetic tape in a few seconds, frantically rewinding it and then playing it back. In these playbacks the quality was usually poor and there was missing information represented by blurring of the image.

These days using high speed analogue digital techniques, you can literally see the sweat droplets coming off our Tennis stars forehead in unbelievable detail!.

See also this article for more details on the different types of ADC’s and their application.

This is all well and good, but powering these suckers and keeping them powered for anything up to 15 years or so is causing real head scratching in the embedded world. So what’s the solution?

Well, with new generation microcontroller devices capable of running of the juice of a lemon or even grapes!, the search is on for new ways to harvest energy.

Energy harvesting commonly refers to gaining energy that would otherwise be wasted.

Piezoelectric harvesting for instance takes advantage of vibrations to excite a mechanical structure at its resonant frequency. This mechanical structure is then attached to a piezoelectric substrate, which will generate electricity, albeit at a very low level.

Piezoelectric Harvesting

IMEC is one company that has taken advantage of this and have succesfully developed a generator that can produce 40-60uW of power. Not huge but enough to power the latest low power micro controllers such as those from TI.  Couple this to something like a Supercapacitor and you have a lifetime supply for your device!.

I am living proof of that as well as many of you out there, that you do not necessarily need a degree in this industry, to be a successful engineer!.

So what are the attributes that make a successful engineer?

Here are some that I consider when hiring potential candidates…

• Qualifications… sure I look at these, but this alone will not screen a candidate out.
• Hobbies. No, it does not have to be in the field of engineering you have studied.
• Work experience. Any!. So long as you have had some. (but not mandatory if your hobbies show a determination to get something done!)
• Hands on… Anything!. OK, so you want to be an engineer but you tinker with cars, yes, that’s cool. It shows that you are not afraid to try your hand at something.

The degree may help, but if you don’t have any practical experience, I’m afraid the industry will probably pass you by unless you are happy to be stuck in automotive/aerospace industries working on the same project for most of your career.

Read this article written by the well respected Jack Ganssle on this very topic, who kindly gave me his permission to publish this article on my site.

For me this statement by Jack rings true….

“We need thinkers and doers, inventors and implementers, designers and troubleshooters.”

It’s not just engineering, it is the thinking. The east are pumping out ‘engineers’ like there is no tomorrow, however there is only a small percentage that I have come across yet that meet the above criteria, but, that will change!.

So over to you Jack…

Do You Need A Degree

A friend went away to college at age 18, for the first time leaving home behind. A scholarship program lined his pockets with cash, enough to pay for tuition, room, and board for a full year.

A few months later he was out, expelled for non-payment of all fees, and a GPA that rivaled those of the students in Animal House. The money somehow turned into parties, parties that kept him a long way from class.

Today he’s a successful mechanical engineer. With no degree he managed to apprentice himself to a startup, and to parley that job into others where his skills showed through, and where enlightened bosses gave him the title and the work he’s so adept at.

Over the years I’ve known others with similar stories, many of which ended on not-so-happy notes. The draft during the Vietnam era was, in a way, a tough burden for many smart people. They came back older, perhaps with families they had to support, and somehow never made it back to college. Many of these people became technicians, bringing their military training to a practical civilian use. Some managed to work themselves up to engineering status. Others were not so lucky.

Another acquaintance breezed through MIT on a full scholarship. Graduating with a feeling that his prestigious scholarship made him very special he started working in aerospace. The company put him on the production line for six months, riveting airplanes together. In those days this outfit put all new engineers in production to teach them the difference between theory and practicality. He came out of it with a new appreciation for what works, and for the problems associated with manufacturing. I’ve always thought this an especially enlightened way to introduce new graduates to the harsh realities of the physical world.

Most of today’s new engineering graduates do have some experience with tools and methods. Schools now have them build things, test things, and in general act like a real engineer. Still, it seems the practical aspects are subjugated to theoretical ones. You really don’t know much about programming till you’ve completely hosed a 10,000 line project, and you know little about hardware till you’ve designed, built, and somehow troubleshot a complex board.

Experience is a critical part of the engineering education, one that’s pretty much impossible to impart in the environment of a university. We’re still much like the blacksmith of old, who started his career as an apprentice, and who ends it working with apprentices, training them over the truth of a hot fire. Book learning is very important, but in the end we’re paid for what we can do.

In my career I’ve worked with lots of engineers, most with sheepskins, but many without. Both groups have had winners and losers. The non-degreed folks, though, generally come up a very different path, earning their “engineering” title only after years as a technician. This career path has a tremendous amount of value, as it’s tempered in the forge of more hands-on experience than most of their BSEE-laden bosses.

Technicians are masters of making things. They are expert solderers - something far too few engineers ever master. A good tech can burn a PAL, assemble a board, and use a milling machine. The best - those bound for an engineering career - are wonderfully adept troubleshooters, masters of the scope. Since technicians spend their lives daily working intimately with circuits, some develop an uncanny understanding of electronic behavior.

Some companies won’t let engineers touch a product. A tech is the developer’s hands and senses. Though the engineer knows more about what the system should do, I imagine the techs have a deeper understanding of what it does do.

Too many of us view our profession parochially, somehow feeling that college is the only route to design. Part of this probably stems from the education itself, where instructors without doctorates cannot become full professors. Some comes from our fascination with honors and fancy certificates. Doctors and lawyers plaster degrees and awards over the walls to impress clients… which implies that we, the public, are indeed impressed by these paper kudos.

These same doctors and lawyers have very effective professional associations that limits entry in the field only to those people with a degree - from a school approved by the association. It’s a clever way to maximize salaries via anti-competitive measures.

Electronics is very different. We’re in a much younger field, where a bit of the anarchy of the wild west still reigns. More so than in other professions we’re judged on our ability and our performance. If you can crank working designs out at warp speed, then who cares what your scholastic record shows?

School Skills

And yet, our creations get more complex every day. A 1975-era embedded system pushed the edge of technology at 4 MHz, yet required little of the theoretical knowledge we got in college. One needed the ability to read a data book, the experience to know how to create circuits, and the ability to make the silly thing work.

Today’s designs are different. We battle Maxwell’s equations every time we propagate a fast signal more than a few inches. Our products’ algorithms rely on Fourier Transforms and other advanced mathematical concepts. After resisting all of the math they fed us, now I feel a little bit like the teenager coming of age - our professors, like our parents, were right after all!

Other neglected parts of a college education are becoming important. One of the most crucial: writing skills. Engineers are notoriously poor communicators, yet we’re the folks building the communications age. After decades of decline, writing has assumed a new importance in the form email. We’re judged by our composition skills every time we toss off a message.

Of course, few engineering programs focus on writing. It’s as if the intent is to produce development androids without the skills needed to “interface” with the rest of the world.

Occasionally we hear talk of turning engineering education into more of a vocational program. Train students to design systems and nothing else! The model fits well into the 90s frenetic preoccupation with getting results today, and the future be damned. If we agree that a tech, who has a VoTech-like education, could be a good engineer, then perhaps there’s value to revolutionizing our schools.

Yet, I worry for the future of our profession. Several forces are shaping profound and scary changes.

The first is simply the breathtaking rate of change. Every 3 years or so it seems we’re in a totally new sort of technology. This will only accelerate, which means the engineer of the future will either have a 3 year long career, or will become adept at anticipating the change and at embracing change. More than anything it means we have to re-educate ourselves daily. By reading EDN today you’re working on your future.

Yet I talk to engineers everyday who spend little to no time keeping current.

Time to market is another force that will change the profession. When designing a product there’s no time to learn how to do it, or to master the product’s technology. Companies want experts now. Yet how can you be an expert at new technology? This is one reason we see so many consultants working in development efforts - they (effectively or otherwise) bring new knowledge to bear immediately. Enlightened management will find a way to transfer this knowledge to the core employees. Sadly, too many can’t see beyond getting the product out the door, never investing in growing their skill sets.

Finally, we see a serious pigeon-holing of skills. Are you good at x? Then do x! Do it forever! We can always get a new kid to work on the next project - after all, you’re the x expert!

The complexity of software will only make this worse. Design a product, get it out the door, and there’s a good chance you’ll be involved in its maintenance forever.

You’ve got to take charge of your career. Manage it. Keep learning and stretching your skill set.

But I wonder how many techs-turned-engineers have the background to keep up in this rapidly advancing world. Similarly, I wonder how many college-educated designers remember enough math to understand what’s going on. I did a survey recently of several graduate engineers. None could integrate a simple function. None remembered much about the transfer function of a transistor. Though these were digital folks who work with ICs, does this mean that the background and the theory drummed into them so long ago is worthless?

Does it imply only the youngest, those who haven’t had time to forget, should work on the newest and the most complex systems?

I wish I knew the answer. I’ve tried not to discriminate on the basis of a degree, having had some wonderful experiences with very smart, very hard working people who became engineers by the force of their will. But over time I see fewer of these. More and more resumes are filled with BS, CS, several minors, one or more masters, and the like. There’s a competitive pressure that raises the stakes in job seeking. If one degree is good, we seem to think more is better.

Clearly, any large organization will screen non-degreed people out before they can demonstrate their (possibly) outrageous abilities.

Engineering is a very diverse discipline. We need thinkers and doers, inventors and implementers, designers and troubleshooters. Sometimes one person contains all of these skills, though more often a team comes together to complement each others’ skills. The whole is greater than the parts.

When it’s time to hire most of us look for the standard requirements, probably including some sort of degree. I like to use the SWAN model: Smart, Works hard, Ambitious, and Nice. Though hard to gauge at an interview, these qualities almost guarantee a decent worker. When hiring a non-entry-level person, the SWAN model, coupled with what they’ve done in the past, is a far better indicator of success than any sheepskin.

Conclusion

As someone who rejects our fascination with form over substance, I think that good, non-degreed engineers are a valuable asset only a fool would reject. However, not getting a degree is clearly a mistake. One just cannot compete in the job market without this prerequisite.

I know - I dropped out of college three courses short of a BSEE.

For older folks who, by circumstance or bad planning did not complete college, look at other degree options. Check out High Technology Degree Alternatives, by Joel Butler, (ISBN 0-912045-61-2) 1994, Professional Publications. It’s full of ideas about getting a degree without quitting your job or spending a lot of money.

Jack can be found all over the www but I recommend highly that you subscribe to his no nonsense newsletter.

During my time in the embedded industry I have thankfully, enjoyed many successes (I wouldn’t still be in the industry otherwise!) but along the way I have made some mistakes but gained a heck of a lot out of the experience.

For example there was a time when micro controllers came only in OTP (one time programmable) versions, Non of this re programmable ‘flash’ stuff we have today.

Being OTP meant that, you needed to get that code right or else!. Certainly this is not an issue if you are producing a handful of prototypes, but if you are doing a decent production or pre production run, you can easily end up with a stack of boards which will be good for nothing!.

I faced this exact issue on a product of mine. We had produced 1000 pcbs all with one of the Microchip Inc PIC12C509 micro controllers on board. Designed in such a way that the devices could be programmed in circuit after board assembly.

The product in question interfaced to a special type of ‘touch’ switch which needed debouncing. Unfortunately in my haste, I forgot to set the default value for the debounce time to a reasonable value making the switch ultra sensitive.

Arrghh! DISASTER! Well no, not quite.

As stated above, these devices are OTP only so there was no chance of erase and reprogram!, but there was still a way. Even though erasure was not an option, programming un programmed bits was still available.

As some of you realize, when a device is un programmed (shipped from the factory) all its bits are normally set to ‘1′. Once programmed the bit is set to a ‘0′. (i.e. If the instruction/data byte needs that bit set to ‘0′…I can get into convoluted discussion here, but I shall try to refrain!)

So what? you ask. Well, if I could find where exactly in program memory the debounce value is referenced, maybe I can toggle some of the un programmed bits to a usuable debounce value. This was not as simple as I thought, due to the fact that I needed to raise the debounce value, meaning that I needed more bits set not unset. (Think about it a bit…)

Luckily for me though, the next byte after the debounce value was a return instruction followed by some unprogrammed bytes. This allowed me to change both the debounce value and the return instructions with  NOP’s instruction, letting the program now skip through to the un programmed bytes where I could enter a new value and a new return instruction.

OK, so problem solved. But it may have been a different result for those who do not understand the underlying processes of what is a bit and what it means to be programmed or un programmed.

Anyway, that said, I would like to hear your ‘great escape’ from failure stories. Please drop me a line here and share your experiences.

“The kit includes a small board that has a CryptoController chip connected to an AVR® microprocessor, a 9-volt battery alternate supply cable, all the necessary USB cables, and USB flash drive containing documentation and demonstration software.”

All you have to do is sign up to register your interest and you are in the draw to win the kit valued at U$99.

For more competitions and giveaways like this, please sign up to my RSS feed, then head over to Atmel and register your details with their ‘CryptoController Development Kit Registration Form‘ for your chance to win!

Good luck!.

Dale.

Then the “Microsoft Dare to Dream Different challenge” competition just announced by Microsoft is just the ticket.

“If your entry is one of the best you will share in the $50,000 in prizes and numerous other benefits up for grabs.

Interested in converting your creation into a commercial product? Win in our professional category and automatically become a .NET Micro Framework business partner.

Care more about fame than fortune? Win in our hobbyist category and get the opportunity to have your device in a Microsoft maketing campaign!”

Sign up to our RSS feed to get the latest on new competitions and free hardware offers then head on over to the Microsoft Dare to Dream Different challenge.

We will be ‘test driving’ the SDK in future articles and welcome any feedback with your experiences.