The Atom was the reason why Intel had to sell the XScale division. Unfortunately the XScale CPU wasn't all it should have been, lacking debug capability or the performance leap promised by its StrongARM heritage. While Intel sold a few chips to people for WinCE PDAs, and even a few Motorola cellphones, the market was small compared to that available to TI and the like. Free from its ownership of a competing architecture, one which has wiped the floor with Intel, its execs obviously feel comfortable letting rip at ARM. Intel is no-doubt hugely frustrated at its inability to compete in the fast-growing cellphone market, and the Apple iPhone is just another sign of ARM's dominance in this sector. So here is the comment I'm referring to:

Kedia didn't just stop at the iPhone, claiming ARM was a malaise afflicting smartphones in general. "The smartphone of today is not very smart," he said. "The problem they have today is they use ARM." Wall believed the situation was unlikely to change anytime soon, saying Intel was two years ahead of the rival company. He didn't believe fast, full internet would receive a début with ARM-based devices in the near future. "Even if they do have full capability, the performance will be so poor," he said.
Of course this guy is just venting, during a trip to Taiwan. Perhaps he met with a number of potential customers there who all told him they were using ARM and very happy with it.
But also, it simply isn't true. Tom's Hardware shows Atom's power consumption (for CPU alone) of about 2.5W, with 5W including the required companion chip. We should point out, though, that the two chipsets to be used with the Atom N200s are power users: the Atom 230s use an i945GC that consumes 22W (4W for the CPU) and the Atom N270s ship with an i945GSE that burns 5.5W (2.4W for the CPU).
This is for a 1.6GHz CPU. By comparison the OMAP3530, a dual core 600MHz CPU with integrated video DSP, 3D graphics, NEON SIMD machine, DDR interface (i.e. Atom + support chip) consumes under 2W total (and that's the maximum from the datasheet and the Beagle board - with power management OFF!). It is a mystery why Intel chips consume so much power. Some say it is the Byzantine x86 instruction set. Others say that Intel aims for speed rather than power. Who knows... So in terms of power consumption, Intel isn't even able to play the game yet. It is perhaps 3-5 years behind ARM on this one. The claim that the Internet isn't usable on an ARM CPU is also bogus. From what little I have seen of the iPhone it seems usable enough. My Nokia E90 certainly runs ok on the web, although I agree it could do with more speed (it is an ARM11 design). I think Intel will be shocked at the capability of the Cortex-A8 devices when they come out in the new year. Of course Intel needs to attack ARM - ARM owns the lower power market space and it is the only way that Intel can make inroads into it. But Intel needs to get its products in order first. Perhaps Intel should swallow its pride, take an ARM architectural license and put its A team on the project. The C team didn't do a great job, but everyone knows Intel has great chip engineers - just look at the Pentium range. Take away the x86 baggage and who knows what might be achieved?

When using the Realview ICE, there are normally portions of the development that are often repeated. Loading and executing a specific image for example, or configuring the SDRAM controller to allow normal development to proceed. These are typically done either in a simple compiled program, or using the inbuilt scripting available in the Realview Debugger. When using the graphical environment however, even when using a single executable, the time taken to click on all the buttons to execute the task can seem laborious. However there is another method available - using the RDDI network protocol to communicate directly with the ICE unit. This protocol allows for all of the standard JTAG operations to be performed automatically from code. At Bluewater we have developed a minimal scripting interface which communicates over this API to automate the tasks which we often perform. This means that with a single click we can bring up a completely un-programmed board into a running state, upload the latest version of our code, and begin executing it with no further interaction. When dealing with a large variety of different development boards, this can be vital in ensuring that information on how to deal with each one is not lost - the script provides all the information necessary. As the details of the actual JTAG operations are still left with the ICE, all the performance advantages of the ICE are still in effect. Operations available from the RDDI network protocol include:

  • Resetting the target
  • Setting & retrieving register values
  • Uploading images to memory
  • Downloading images from memory
A sample library is provided by ARM for these purposes, available from http://www.arm.com/products/DevTools/RDDIRVI.html.

While working on DDR memory routing on our Snapper-DV board, which is now using a Texas Instruments (TI) OMAP3530 applications processor, all DDR memory bus lines, including control signals, are terminated with series resistors in between the processor going to the two balance-T DDR ICs. As with all routing that involves DDR, extensive length matching is normally applied to these memory traces (which are further classified into classes per their function). Normally, Cadence Allegro Performance tool via Constraint Manager can handle length matching of traces point-to-point (net) very well.  But with series termination resistors in between, it adds complication because these resistors have to be inerpreted as part of the net connecting the processor to the DDR ICs (see figure below) and thus have to be included in the length matching. When the path of a net traverses a discrete device (resistor, inductor or capacitor), each net segment is represented by an individual net entity (net1, net2) and this whole length is called "Extended Nets" or Xnets. CPU ------------ series term resistors ------------ DDR ICs net1                                          net2 |-------- Extended Nets (Xnets) ---------| Cadence handles Xnets very well and it's very well documented using their high-end schematic/PCB layout and simulation tools, which are very costly. Xnets have to be created so that Constraint Manager can interpret this as a whole trace/track length for matching.  These can only be created by attaching a "signal model" on the discrete device (resistor in our case) and this is a very easy step with Cadence high-end tools front-to-back flow as it is well documented. But with a basic ConceptHDL and Allegro Performance tools, it took some fiddling around to achieve the task. Though the Allegro Performance datasheet shows that Xnets are supported, getting the Constraint Manager to recognize the Xnets was not easy. Assigning a "signal_model" property using the "Edit>Properties" menu was easy, but it didn't create the Xnet that was expected. There are no explicit instructions on how to do this on this medium-flavored tool. The trick was to go through "Setup Advisor" until "SI Model Assignments" and assign the "signal_model" property to the resistors. This procedure worked, Xnets were created, Constraint Manager did recognize these and length matching can now be handled optimally and with ease. In summary, and from experience with using schematic/PCB software tools not just from Cadence, it just doesn't end going thorugh the documentation of using the tool.  There's a lot more to it when using and applying the tools in real life work.

In preparation for manufacturing a large number of Snapper CL15 modules, we have been developing an automated test system for quickly and accurately finding assembly faults in Snapper CL15 modules.  The test system will be sent to the manufacturer so that the modules can be tested and, if necessary, repaired at the point of assembly. In the past we have used our Autotester software, combined with a Rig 200 baseboard for testing Snapper modules.  While this approach works reasonably well, it has a number of limitations which make in unsuitable for this task:

  • It is too interactive.  Many of the tests require user interaction or confirmation. For example, the audio test requires the user to confirm that a sound was played correctly, and the USB tests require the user to insert and remove a USB device.  For large builds this interaction becomes both tedious and error prone.
  • It cannot accurately find faults.  A failed test in the Autotester only tells the user which sub-system is faulty, but not where the specific problem is. For example, the video sub-system of the Snapper CL15 comprises of more than 20 pins, but a failed video test in the Autotester does not give any information about which of these may be faulty.
  • The Rig 200 baseboard does not expose all of the features of the Snapper CL15 in an easy to test way.  While the major features of the Snapper CL15 are accessible on the Rig 200 baseboard, many of them require some additional hardware to actually test the functionality.
To solve these problems, we have developed the Snapper CL15 test jig.  The test jig is a standard Snapper CL15 baseboard which has been designed to fully automate the testing of all of the Snapper CL15 features. In the event of a failure, very specific information about the nature of the fault, often referencing a single pin, is given. The problem of requiring external hardware for testing some peripherals is solved by having an FPGA which can monitor and drive pins on the Snapper CL15. The FPGA enables tests which previously required user interaction, such as video test, to be fully automated. For the video testing, the Snapper CL15 runs an application which configures a video mode and displays a test pattern.  The FPGA has registers which contain information such as the number of clocks per line and the sum of the pixel data in the frame. The software running on the Snapper CL15 can verify that this information is correct. Many of the test procedures use loop-backs so that no user interaction is required. For example, the audio tests, which in the Autotester setup required a user confirmation that sound played correctly, loop the line-out to the line-in via an analogue switch. After initially testing that the left and right capture channels are working correctly by feeding a 1kHz (generated by the baseboard) to them, the line-out and high-power out are tested by looping them back to the line-in and comparing the captured audio with what was played. The test jig system will be able to fully test a Snapper CL15 module in around 2-3 minutes, with no user interaction other than insterting the Snapper CL15 module and checking the result of the test. Because the information about failures is highly specific, it enables the manufacturer to quickly find and correct any assembly faults with the modules.

As you know, Bluewater recently participated in Sky Challenge, having contributed by developing the heads-up display system which the pilot used for flying the course , and co-development of a microwave communication link which sends the positional data for the aircraft to the ground. Here are a few more links that we like that show you what Sky Challenge is all about. http://news.bbc.co.uk/1/hi/technology/7633110.stm http://news.bbc.co.uk/2/hi/technology/7651327.stm http://www.astrofiammante.net/blog/sky-challenge-better-than-the-nintendo-wii-post279/