Control Matters
SPLat Controls' aperiodic newsletter

21 Jan 10
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The need for speed

When we made the first SPLat controller, back in 1995, it had 1999 bytes of program memory. We never expected it all to be used. After all, the controller had a repertoire of just 30 instructions, and was intended for simple timing and sequencing applications. At that time the program download system we implemented seemed perfectly adequate - it would download even a "large" program in 3 or 4 seconds.

SPLat now has 400+ instructions in its repertoire and 25K or so of program memory. We, and many customers, are making sophisticated applications with 10K or 20K or more of program (SPLat's memory utilization is extremely efficient due to its Virtual Machine architecture, so 20K in SPLat is equivalent to 100K+ in some other controller languages - see our language comparison). The time to download a program has dragged out to up to 3 minutes, which seems like an eternity when you are just sitting watching it.

So we have done something about it (I would hardly be writing this if we hadn't, would I?). The latest release of SPLat/PC (32-bit version) has a much faster program download protocol. In fact, we measured it at 29-point-something times faster on an 8K test program. Combined with the 6x faster translation (compile), the total "Translate and go" time for our test program went from 104 seconds to 4.5 seconds. You can download the latest SPLat/PC here.

The faster download requires new firmware in the controller. There is upgraded firmware (reFlash files) available for all current model standard controllers (CC18, SL100, MS120, MMi202) here.

David Stonier-Gibson

In control - Stuff about or related to control systems

Help stamp out bad code!

If you are worried about your carbon footprint you can buy carbon offsets. Now there is also a solution for those of you who worry about writing bad program code. The Alliance for Code Excellence have a scheme that allows you to buy offsets for any bad lines of code you may write. The revenue is used to support open source software projects. Now you can experience guilt free flying and guilt free coding! 

Alliance for Code Excellence 

Out of control - Nothing much to do with controls, (but interesting)

Beware power factor (and other energy saving) scams!

If you google for Power Factor, chances are that very near the top of the results will be a small article I wrote back in the mid-90s. Through shear age my article has percolated to the top of the listings. While this article is interesting and educational, it has very little commercial value for my company. So in February last year I decided to run Google adverts on the page, to try and make at least some lunch money out of it (Results to date: About $120, below the threshold where Google actually pay me).

During the Christmas break I received an email from a gentleman in California who has particular mission to stamp out scams related to energy saving gadgets. He pointed out to me that some of the adverts running on my power factor page were, in fact, for rip-off products. These products claim to save householders money on their electricity bills by improving the overall power factor of their home electricity usage.

While the power companies will charge large industrial and commercial users more for poor power factor, that does not happen to domestic users. The electricity meter in your home registers true power, and that's what you get charged for. Power factor, and reactive power (wattless watts) do not affect domestic electricity bills.

Any device that claims to significantly reduce domestic electricity bills by improving power factor is a scam.

I still run Google adverts on the power factor page. However, all known scam products have been blacklisted. This includes, incidentally, offerings like $50 plans for a gadget you can build for $200 that will provide you endless free energy, perpetual motion machines, systems that power cars from water, etc. The laws of thermodynamics are immutable.

Power Factor: Dissipating the Myths  

You can now program SPLat hardware in C, with our free RTOS. Click here for details.

Q:What's the difference between an engineer and a computer scientist?

A:An engineer thinks there's 1000 bytes in a kilobyte, and a computer scientist thinks there's 1024 meters in a kilometer..

Writing in C or C++ is like running a chain saw with all the safety guards removed. .
Bob Gray 

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Copyright 2010 SPLat Controls Pty Ltd. This communication does not constitute professional advice