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There are 10 types of people in this world....... Those that understand binary and those that don't.

X-Plane LogoWhile developing some in-plane software, we recently had to determine the best way to do end-to-end testing of our system. Unfortunately access to an actual plane was limited, and obviously both time consuming and costly. Fortunately we discovered the hugely extensible X-Plane. It provides a highly detailed flight environment (the scenery data requires 6 DVDs), and allows for easy writing of plugins to manipulate the environment, providing full access to all of the plane controls & environment. This allowed us to easily test our system on the desk, in a completely simulated environment, whilst still testing the entire system.

Question: How many Software Engineers does it take to change a light bulb........? Answer: None. Its a Hardware problem.

Recently I was working on the power supply for our upcoming SnapperDV board. I needed a small efficient power supply to generate 1.3, 1.8 and 3.3volts for TIs TMS320DM355 which is the CPU on SnapperDV. On our Snapper270 design a TPS65021 is used which is a tripple DC/DC converter with two LDOs. Something similar would be ideal. After looking at all the options, strangely the same power supply chip seemed most suitable. Current limit looked good, the power fail detection comparators can be used instead for voltage sequencing, VRTC can be used as a system monitor voltage, the nINT output can be used as a voltage supervisor, The LDO can be used to power the CPUs PLL. It actually works out to be a very good fit - even though it is recommended for a PXA270 series CPU and it is not being used 'as intended'. Taken into account that we have these in stock given they are used on our SN270 product and it looks to be a very good proposition indeed.

Apple was the company, in 1990, which put the money up for the formation of ARM. Acorn put up the founding staff and the technology. Apple's thinking then was that ARM would power the Newton, which would revolutionise the world. Well we know what happened with the Newton. Looking at it now the main thing that strikes me is how enormous it was. And I can't forget a comment made by a colleague that the handwriting recognition software on the Newton was the most efficient cache-flushing algorithm known to man. But anyway, my point is that Apple had an associate from ARM since the first. And now there is a rumour that Apple has perhaps purchased an architecture licence from ARM, meaning that it can implement its own variant of the microarchitecture. The evidence is sketchy so far:

[Talking about DEC who implemented StrongARM based on an architectural license] And who was the engineer that had led the Digital Equipment team that developed StrongARM under an architectural license? It was Dan Dobberpuhl, subsequently CEO of Palo Alto Semiconductor Inc. With the recent acquisition of P.A. Semi by Apple, Dobberpuhl has become an Apple employee. And perhaps now, with ARM's disclosure, we are beginning to see why Apple was interested in Dobberpuhl and his capable design team.
[The Apple rumour mill is running hard also]. And this is supposedly the motivation:
The Apple iPhone is thought to have as many as five ARM processor cores inside it, but those processor cores are contained in multiple chips from several different chip vendors. Wouldn't that be perfect for rationalizing into a multicore ARM architecture, if Apple chose to go down that route?
Certainly there is merit in this - it is what Nokia have done with their communicator, which, believe it or not, used to have a 386 CPU and an ARM. The 386 was for keeping your hand warm. Most Bluetooth and WiFi devices include an ARM core. The iPhone is ARM11-based, not the latest thing but still pretty nifty. Sadly, if Apple do produce an amazing new microarchitecture, it's unlikely we will see it in anything other than an Apple product. On the plus side, as StrongARM vanished, the prize for building a high performance ARM chip, well out in front of the industry, has not been awarded for years.