tant for my low-energy application - suspend
current or active current?” The answer depends
on the active time duty cycle. Some energy-
friendly ARM Cortex-M class MCUs can con-
sume as little as 110 μA/MHz in active mode
and 900nA in deep sleep with brown-out de-
tection active, which means suspend and active
operation contribute equally at 0.1% duty
cycle at 8 MHz operation. Navigating MCU
vendor datasheets to compare performance
for low-energy applications can be a challenge.
Look for MCU suppliers that offer energy esti-
mation and profiling tools and offer excellent
suspend and active current performance.
Another frequently asked question concerns
the choice of MCU bit size for IoT applications:
“When should I consider using an 8-bit MCU
instead of a 32-bit solution for my end node
application? Why not migrate to a modern 32-
bit MCU based on an ARM Cortex-M archi-
tecture that supports expanded memory re-
quirements, native 32-bit math and advanced
peripherals?” For many performance-intensive
IoT applications, the 32-bit choice is of course
the right answer, particularly where portability
and future platform reuse are key concerns.
However, for end-node applications where the
goal is to fit in the absolute smallest footprint,
run a lightweight RF stack, or offload compu-
tation tasks from the main MCU, a streamlined
and highly optimized 8-bit solution is often
the right answer.
A common misconception of an 8-bit archi-
tecture is that it suffers in from low code
density. In reality, this is true only when at-
tempting 16- or 32-bit math. Control applica-
tions such as those found in offloading the
main processor do not suffer from low density,
and in fact, because 8-bit MCUs have very
little overhead code, overall code density for
control-type functions is higher than equivalent
functions implemented on 32-bit MCUs.
Another common misconception is that 32-
bit MCU pricing is comparable to 8-bit op-
tions. Developers will hear this from MCU
suppliers that are no longer investing in an 8-
bit portfolio or competitive in the 8-bit market.
The reality is that the 32-bit architecture and
peripherals are significantly larger in gate
count than 8-bit architectures and consume
more silicon area when compared to 8-bit so-
lutions in the same process geometry. Moving
to a smaller process geometry shrinks the dig-
ital portion (which is about half of a typical
MCU) and increases the system cost. When
considering a comprehensive IoT solution
provider, look for MCU vendors that are ac-
tively investing in both 8-bit and 32-bit MCU
portfolios, and you will find the most flexible
MCU options, the best technical solutions
and the best pricing.
The IoT is the vision of a road to a hyper-con-
nected world in which end users have dramat-
ically expanded knowledge and control of
their environments – at home, at work and on
the road wherever they may be. Elegantly de-
signed and innovative IoT connected devices,
apps and cloud services will be most successful
in driving the IoT revolution. IoT end nodes
and gateways that offer the best combination
of energy efficiency, performance, cost-effec-
tiveness and appealing features– regardless of
MCU bit size – will be in the driver’s seat in
the race to our IoT future. Are you ready?
June 2014
28
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NTERNET
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OF
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HINGS
Figure 4. Advanced sensor node architecture
Rutronik offers M2M SIM cards and chips
from Telit m2mAIR
As of now, customers can acquire Telit
m2mAIR M2M SIM cards and chips through
Rutronik Elektronische Bauelemente. With ex-
tensive roaming options even within the host
country, SIM management, security features
as well as technical support and a troubleshoot-
ing service, these SIMs provide a complete, se-
cure and cost-effective solution for all types of
M2M applications while maintaining absolute
control over costs. In addition to the standard
SIM cards, models with larger temperature
ranges as well as soldered SIM chips are also
available through Rutronik.
Applied Informatics: software building
blocks for the IoT
Making an embedded system ready for the
Internet of Things is a challenging task. Com-
plex requirements related to connectivity, in-
teroperability and especially security must be
met. A good way to deal with complexity is to
rely on existing, industry-proven building
blocks. Applied Informatics has developed the
IoT Framework, a comprehensive, integrated
set of software building blocks for the devel-
opment of applications targeting IoT gateway
devices.
Avnet Memec: IoT at the centre of
growth strategies
Avnet Memecis placing the Internet of Things,
at the centre of its growth strategies. Internet
of Things - often identified by the term Ma-
chine-To-Machine - is an ecosystem of remote
applications and services based on sensors,
actuators and controls connected to an IP
network. There are huge market opportunities:
estimates suggest that by 2020, 39% of the 23
billion web-connected devices will be IoT so-
lutions, way higher than mobile phones and
portable devices.
RUTRONIK: IoT gateway solutions from
Advantech and Intel
Advantech releases a new, comprehensive IoT
solution: the UTX-3115 fanless and wide-temp
embedded box coupled with the Intel Gateway
Solutions for the Internet of Things. It simpli-
fies customer deployment of IoT products
and allows secure data aggregation, filtering
and analysis from edge devices to the cloud
through WiFi and/or 4G technologies. The
out-of-the-box solution with a pre-integrated
software and hardware platform containing a
Linux operating system, security and manage-
ment features, is available at distributor Rutronik
as of now.
Conrad supports open source IoT starter
kit ‘WunderBar’
Conrad is working exclusively with Berlin
based start-up company relayr (iThings4U
GmbH) to support the development and
launch of the Open Source IoT starter kit
‘WunderBar’. The WunderBar IoT starter kit
together with the relayr Open Sensor Cloud
platform allows software application developers
to quickly and easily begin working on wireless
applications and prototype building based on
data gathered from the physical world without
needing to learn about hardware. The platform
includes software development kits for iOS,
Android and Node.js.
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