RaspberryPi for professional use

Raspberry foundation will release a new CPU-module with form-factor of SODIMM-memory.

Raspberry Pi has become extremely popular among hobbyists. The win of the concept is not because of it's technological marvel, but essentially because of the great ecosystem and support.

Raspberry Pi is known to be used as a basis of some commercial embedded solutions as well, even if RPi as such is not very suitable for the purpose: connectors are inconveniently located at all edges of the board, limited extension header, and lack of mechanical support. Compare for example to BeagleBone Black, which is much better suitable to be used as a part of other products.

A week ago, Raspberry foundation published their plans to release a new CPU-module within the summer. The module has form-factor of SODIMM memory module, perhaps the most popular format of CPU-modules at the day. The module has Flash-memory on board, thus separate SD-memory card is not necessary.

Picture of the RPi CPU-module from RaspberryPi web site.

For sure, this new product is intended for professional use. Very few hobbyist has capability to design and manufacture motherboards of their own. Perhaps the community will help here and some application specific motherboards will be available in the future.

For professional purposes this module is good, as now it does make sense to have RPi in your design. Why RPi module instead of some other CPU module? First of all, RPi has the winning ecosystem, having software support that exceeds any commercial vendor. Secondly, RPi modules are expected to be rather inexpensive. Retail price is not published yet, but for sure it will be lower than the Raspberry SBC models available at the day.

For what RPi is then good for? The Broadcom BCM2835 SoC is actually a GPU with added general purpose CPU core (ARM9), thus it can do graphics decoding and 3D rendering efficiently by hardware. Broadcom recently released more specifications of the GPU side, thus more open drivers are expected soon. So as an answer,  RPi module is suitable for any embedded products having local 2D/3D graphical display for HMI in use.

According to unverified sources, Broadcom is also planning to start selling the module, as in it's ripped-down format it only contains silicon IP of Broadcom's own. According to the same source, the current RaspberryPi does not use the SoC in most energy efficient way, and perhaps in this new product the power consumption will be lowered down to mobile phone level.

Availability via Broadcom is essential to have creditability of availability good enough for any commercial products with long life-cycles like in case of industrial and medical applications.  

Generic technology exhibitions loosing popularity

Scandinavian Electronics Event was organized in Stockholm Kista within this week.

In Sweden the same effect is clearly seen as in Germany, which I reported in my previous posting about Hannover messe.

Scandinavian Electronics Event is rather generic event in domain of electronics; there are PCBA manufacturing machine makers, EMS providers, component dealers, silicon technology providers, some software suppliers, and consulting houses in one place without clear focus. Other ends of the convention hall are like day and night.

My company attended S.E.E. as an exhibitor some years back, already at that time it was disappointment, with very little relevant contacts and low number of visitor. At that time there was merely 5000 visitors during the 3 day show. We decided not to go anymore.

According to published numbers of two first days, it looks like the total number of visitors will decrease down to 4000. That's definitely too little to justify a three-day event. I discussed with some exhibitors familiar to me, and they told it's not only disappoiment, but also a disaster to put so much effort for pretty much noting.

Meanwhile Scandinavian Electronics Event is struggling for it's existence, Embedded Conference Scandinavia reported 50% gain in number of visitors last time. ECS is smaller than SEE, but very well focused. Every visitor is potentially relevant contact. My company will attend ECS as an exhibitor this year, just like we have done for the previous 5 years.  And once again I will prepare a presentation to be held there. ECS will be organized in the very same place at Kista mässan in November.

Why does it goes like that? Quite obviously at the Internet era, trade fairs and exhibitions are not needed to get information about new product releases and what's going on in general. Why are smaller tightly focused professional events gaining popularity then? It's not about new product information, but getting and maintaining professional contacts, socializing, "to see and to be seen among professionals of your kind", somehow comparable to academic conferences.

Maschinenbau

Why does German industry so well at the moment?

German industry has long tradition of "Maschinenbau" (machine construction). Today, this is seen by the huge number of companies designing and constructing machinery of all kind.

Many of those Maschinenbau companies are focusing on certain very narrow and high-tech area, typically making machines which are used in making other machines. Meanwhile other industries moved manufacturing to Asia, Maschinenbau companies have pretty much kept production in their own hands locally.

Typically these products are expensive and manufactured in small volumes, thus the cost benefit of mass production in Asia is not achieved. More important is to have highly skilled workers in assembly, and have fast feedback cycle from production back to the design department.

At the Hannover messe, I spotted number of products designed by my company, as usually. Among those customer references, I have picked up here couple of good examples of the spirit of Maschinenbau.

Beamex MC6 field calibrator.

Beamex provides world class field calibrators and communicators. Beamex is known for high-accuracy calibrators, and is the market leader on that specific sector. Not only sensors on field, but also the calibrator by itself needs to be calibrated every then and now. After-sales service is important part of the business. Needles to say that the company is doing very well and breaks it's own records year after year.

Epec 6107 Display Unit with Cortex-A9 multi-core CPU.

Epec design and manufacture control systems for vehicle environments, intended for companies how construct professional moving working machines like harvesters for example. Epec products are especially designed for hars environments, including vibration, moisture, and very wide temperature range. Epec is also doing very well, even if their business is more sensitive to the turbulence of global economy.

These two Finnish companies are good examples of why the German industry is doing so well. By focusing on very high tech domain and  having production of their own, this kind of companies are not threatened by Asian competition, but instead they are exporting to China in fact.

Hannover messe

Once again, it's the time of the world biggest industrial fair in Hanover within this week.

Digital industry, Industrial internet, or Industry 4.0 as German goverment calls it, is one of the leading themes of the event. It's pretty much in line with Embedded World in Nuremberg having Internet of Things as the leading theme. It's all about smart and connected world.

As being in Germany, automotive industry has strong position, of course. Electric cars are especially in the center of interest. Germans are known for their interest towards sustainable economy, one can see windmill parks and solar cell plants all over the countryside.

Electric and hybrid cars presented by Volkswagen.

Hannover fairground is the largest in the world. However, this year it look's like 30% of convention halls are unused, and the number of exhibitors has decreased from average 6500 to just over 5000. German industry and economy in general are doing well, that's not the reason for deduction.

All in all it looks like this kind of general trade fairs are loosing popularity, and giving space to smaller and more dedicated ones. For example Embedded World reported new record this year, having 15% gain in number of exhibitors and almost 20% gain in number of visitors.

Simple HIL example

Even smallest embedded projects may benefit from HIL approach, as demonstrated in this article.

Hardware In the Loop (HIL) simulation, the way it is described in Wikipedia, is considered as an expensive and time consuming method only applied in development of most complex and safety critical applications, like in automotive or aviation domains. Equipment needed for testing an ECU is expensive for sure, but there is also possibility for more lightweight approach in case of more conventional embedded systems development.

Here is an example from my hobby project. Last Christmas I got my interest to model trains to rise again after 25 years, as told in earlier posting Fully automated model train control. As a part of that, I have implemented a RF control for locomotives with two-way communication, using 868 MHz radio.

Model train, RaspberryPi with Sug-GHz RF dongle and train control unit (green antenna).

The control unit installed inside of the locomotive consists of AVR microcontroller, RFM12 radio module, H-bridge driver for motor, step-down regulator for logic voltage, and interfaces for sensors. The module can accept 9..32 VDC, full bridge rectified power from track.

Block diagram of the locomotive control unit.

Power to the drive motor is controlled by H-bridge with pulse-width modulation (PWM). Tachometer attached to the motor provides square-wave kind of feedback signal. In addition to the tachometer, there is also a odometer in place. The odometer counts track ties with infra-red reflections sensor. The measured signal from odometer is pretty much equal to sinusoidal wave.

Functional principle of the odometer.

Odometer signal is hard to generate mechanically in a testbench, and if driving the train around the railway, it's hard to do any measurements simultaneously. Simulation environment of some sort is definitely needed for software development. National Instruments provides myDAQ and myRIO products for educational purposes. I happened to have a myDAQ box available, thus decided to use that one for my "HIL simulation" environment.

HIL setup with target hardware, NI myDAQ and ISP programming device.

By replacing sensors of the locomotive by analog and digital outputs and delivering the motor drive PWM signal back to myDAQ inputs, I had a full HIL-simulation setup in place. With In-circuit Serial Programming device and RF USB dongle in addition, I had a complete development environment in place.

 

Software development environment.

Now there is no need to drive the train around railroad for software development. I can do everything on my desk with the given setup. Only fine-tuning of PID co-efficients requires testing in real target in final deployment phase.

Now the questions is only how good the plant (physical process) simulation model is? In my case, I just had some delay in feedback from PWM to tachometer. That was good enough for the simple problem given. I didn't had to simulate all the physical phenomena like mass, inertia, friction, etc. The drawback is that testing in real physical environment can not be completely avoided.

What is the lesson here? Even smallest embedded projects can benefit from HIL simulation approach, even if no complete plant model exists. In the case of this example, I claim I got benefits in software development, even if I had to learn LabVIEW programming first. A developer already familiar with the given simulation tool can get benefits much faster.

ARM going the Google way

ARM to dominate them all, including the brand image.

I just did some first programming exercises with the ST Nucleo STM32L0 board, using mbed. From developer point of view, the user experience  was pretty equal to my earlier experiments with Freescale KL25Z board. And that's the point!

There are many similarities in how Google and ARM are building the ecosystem around them, only the timescale is different. Google created Android OS and licensed it to phone manufacturers. Each one of them were allowed to customize it and to highlight their own brand image. Eventually people are purchasing Samsung Android or HTC Android,  not Google Android devices.

Soon Google understood they have lost the control over brand image. To fight back, Google introduced ChromeOS, which is kept tightly in Google's own control. Manufacturers are not allowed to tailor it, and Google has full control over software updates, no matter who is the manufacturer of the hardware. This way consumers are purchasing Google ChromeOS devices, manufactured by company X, Y, or Z.

ARM did the same. First they created the IP, which was then licensed to silicon vendors. It took long time, but little by little ARM managed to get the dominant position in CPU architectures. Even if silicon vendors are promoting ARM architecture, the company itself, ARM Holdings does not benefit much from that. People are talking about TI ARM processors, or Freescale ARM processors, or any other vendor name.

As every manufacturer constructed a different set of peripherals with different APIs around the ARM core,  they are more or less incompatible from software point of view, even if they can in theory run the same code due to the same instruction set. Each vendor provides it's own software library for peripheral access, and developers think micros from different vendors as totally different products, not as members of the one mighty ARM family.

To fight back, ARM has done several manouevre. Already in 2005, ARM acquired Keil, a compiler IDE supplier. That was a clever move, as an IDE can more or less hide the difference in silicon designs. However, Keil is not dominant at the market, there are IAR, Atollic, and many more. Thus ARM didn't got the Google position by that.

Later on, ARM introduced the mbed concept;  one unified programming environment for all the micros, running in ARM cloud. "One IDE to rule them all". Well, mbed is perhaps not targeted to immediately replace all the existing commercial IDEs in use, but it is a way to teach developers that after all, the name of the ARM-based silicon vendor actually doesn't matter, it's all about the software.

Once new generation of developers have adopted the approach, the game is changed. With mbed, we're not talking about an Arduino competitor, but a mind changer.

New micros from ST

ST Microelectronics continues going strong in microcontrollers.

During the first quarter of 2014, ST Microelectronics has released a number of new interesting microcontrollers, including ultra-low-power STM32 L0 series, inexpensive STM32 F0 products, and new a new line of STM32 F4 devices with "Dynamic Efficiency" to balance power consumption and performance.

STM32 Nucleo development board

To general public, perhaps the most interesting new product is the STM32 Nucleo family of affordable mbed-enabled prototyping boards, with Arduino compatible pin headers plus ST specific Morpho extension headers. Prices start from just ten bucks. At the Embedded World in Nuremberg, ST giveaway 10'000 development boards altogether.

Last Wednesday, my company arranged together with ST Microelectronics a HMI Workshop and training session about embedded graphics development with STM32F4 and STemWIN graphics library. STemWIN is a free STM32 specific binary port of popular professional emWin graphics library from Segger. At the end of the free training, participants got with them a free STM32F4 Discovery Kit with 2.4" QVGA TFT color graphics display that they exercised with.

STM32F4-Discovery board

We got 25 participants in the event, which is exactly the number of people the conference room reserved for the purpose can accommodate. So we met our targets for the event first of it's kind. As it was so successful to all stakeholders, for sure we will organize new ones in the future as well.

In general, ST has very strong portfolio in microcontrollers. Among microcontroller designs made in my company within couple of last years, STM32 has been the most common choice, incorporating in more designs than other micros. ST products are known for good silicon quality with little or no design faults or manufacturing defects.

Actually, before the training session held this week, I was not aware of who is the local support FAE of ST, as we have never needed any help. Quality of silicon and documentation is very important factor if you do product development for money, and should meet the expected time frame and budget. Fault chip designs ruins your business. Simply cannot claim ST for any such problems.

Once I have some time for hands-one exercises with the Nucleo L0 board, I will report my experiences here.