Tag Archives: ARM Cortex-M4 MCU

Kanega is like a “wearable OnStar for seniors”


UnaliWear’s latest watch offers discreet support for falls, medication reminders, and a guard against wandering.


Most of you who’ve lived through the late ‘80s and ‘90s can distinctly recollect those Life Alert commercials with Mrs. Fletcher yelling, “Help! I’ve fallen, and I can’t get up!” Lo and behold, the catchphrase would go on to become a pop culture phenomenon throughout the United States. Since then, there have been numerous attempts to develop solutions geared towards providing the elderly real-time support in the event of an emergency, especially when they’re unable to reach a phone. And, as we enter the era of constant connectivity, it’s no wonder more brands are turning to ARM-based wearable technology to help bring senior citizens online.

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Inspired by her own 80-year-old mother who refuses to wear some of today’s bulky emergency alert products, UnaliWear CEO Jean Anne Booth decided to take matters into her own hands. Not only are a number of gadgets available today socially stigmatizing and downright ugly, they’re also limited to use in homes unless tethered to a mobile device — something many seniors do not have in their possession.

Dubbed a “Wearable OnStar for seniors,” Kanega is a stylish watch that provides discrete support for falls, medication reminders and a safeguard against wandering, as well as uses an easy-to-use speech interface rather than buttons. The Bluetooth-enabled wearable — which recently made its Kickstarter debut — is connected to a cellular network, meaning that it isn’t reliant upon Wi-Fi or having to be synced to a smartphone much like the Apple Watch or Samsung Gear.

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Better yet, UnaliWear’s latest product can be worn 24/7 thanks to its waterproof casing. This allows for the band to be used in the shower or bath, where a majority of falls occur. Its well-lit display and other built-in features can even assist with issues that may arise at night, such as trips to bathroom or the kitchen for a snack.

Aesthetically it appears no different than a traditional watch, thereby eliminating the ignominy often associated with “needing” assistance. Instead, it first requests permission to speak by buzzing on a wearer’s wrist — something that will surely come in handy when in public. The device can even communicate over Bluetooth to newer generation hearing aids, as well as serve as a communications gateway for home telemedicine devices.

Shall an emergency arise, voice-activated assistance will connect you directly to a monitor who will confirm assistance should be dispatched to a location. If a user happens to activate help and doesn’t respond immediately, UnaliWear will call an emergency contact first or dispatch local medical assistance, depending on the preferences set.

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At its core, the gadget is based on an Atmel | SMART SAM4L Cortex-M4 MCU and a ATWINC1500 module. While it may appear to be another smartwatch, it’s so much more. Aside from its “work anywhere” support, Kanega packs 200% more battery life, continuous speech recognition, patent-pending quick-swap batteries, GPS for proper tracking, and a 9-axis accelerometer. Detected falls trigger a watch-based query, which significantly reduces false alerts, and eliminate the need to be near a base station or smartphone.

What’s more, data is collected and sent to Verizon’s HIPAA-compliant cloud, which offers an analysis of the wearer’s lifestyle. Artificial intelligence learns the wearer’s lifestyle to determine likelihood of wandering, and updates the information on the watch — including activity and medication reminders — every night while asleep. This also helps a wearer obtain directions home or get help if they happen to stray from home.

Interested in a Kanega for a loved one in your life? Hurry over to its official Kickstarter page, where UnaliWear is currently seeking $100,000. Delivery for early backers is expected to begin in February 2016, while shipments to all other consumers slated for Summer 2016.

UPDATE: UnaliWear has completed a successful crowdfunding campaign, having raised $110,154 from 306 backers.

LifeQ is tapping into the human sensor


In today’s constantly-connected world, there is often a disconnect between raw data collection and sensor management. LifeQ has the answer.


According to LifeQ, who made its debut back at CES 2015, the future of wearables may not actually be wearables but instead the data that they collect. The South African startup is looking to tap into the human sensor by combining two technologies to give people the ability to optimize and improve the condition of the body and live intelligently. This pair of technologies, continuous physiological monitoring and bio-mathematical modeling, provide insights around personal and population-wide health, making it possible to significantly improve decision making for anyone’s well-being.

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We had the chance to catch up with LifeQ executive founder Riaan Conradie along with lead engineer Nicol Carstens to explore the ways in which its Atmel | SMART SAM4L ARM Cortex-M4-based solution will enable wearable device companies, application developers, data scientists and other experts to better monitor, understand and manage physiology, behavior and health. It’s important to note: LifeQ is not a wearables company.

At the moment, computational systems biology is a relatively new field, with only a small group of scientists studying and publishing on the topic. LifeQ’s multi-disciplinary team is pioneering this effort and has a vision of enabling every human being to really understand their own bodies and health, and make decisions based on highly personalized health records and insights.

LifeQ’s technology focuses on highlighting and improving six major verticals in one technological device for users to optimize their health and well-being including: fitness, nutrition, sleep and stress, medical, health and data mining. Given that deep analysis of data isn’t just a one-company task, it will require extensive collaborations to provide meaningful insights. Currently, the startup is partnering with a wide-range of brands to enable them to tap into the LifeQ model specific to their industry.

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In fact, DailyDot reports that LifeQ ended CES 2015 with four partners who will include the company’s technology in their devices in the near future, and another 10 to 15 slated to be onboard by year-end. Among the early partners for implementation is First Alert with its Onelink smartwatch, which will take advantage of LifeQ’s ability to add functionality as it gathers more consumer data in its research cloud.

“Mobile health is following a very similar evolution to weather forecasting, going from simply going outside, through barometers to sophisticated computational forecasting,” explained Conradie. “Just like in weather forecasting, the traditional meteorological recording equipment is still needed, but it’s more about analyzing and using that data.”

Undoubtedly, LifeQ’s data pool will continue to expand as more consumers buy its partners’ wearable gadgets. As companies include these sensors into their next products, information will be sent to the cloud, and the resulting streams will be made available to app developers and device makers. Interested in learning more? Head over to the company’s official page here.

Atmel expands SAM G lineup for wearables and sensor hub management

A year after its debut, we’re excited to share that we’ve expanded our award-winning SAM G series of ARM Cortex-M4-based MCUs with the new SAM G54 and SAM G55.

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Targeting the rapidly emerging Internet of Things (IoT) market for battery-operated devices including wearables, such as fitness bands and smart watches, sensor hub management, healthcare, gateways, bridges, audio devices and much more, the new pair of MCUs deliver the right feature mix including higher performance, ultra-low power, smaller form factors and more SRAM. These two series also pack all the features of the current SAM G family like an Atmel | SMART ARM Cortex-M4 MCU + FPU (floating point unit), integrated sensor fusion algorithms, down to 2.84 x 2.84mm package, high-performance frequency of up to 120MHz, ultra-low power down to 102µA/MHz in active mode, and down to 5µs wake-up.

Among the other key features for the new SAM G series:

  • High-performance throughput and efficiency with a Cortex M4-based MCU and FPU
  • Up to 512KB of Flash and up to 160KB of SRAM
  • SRAM power banking
  • Down to 2.84 X 2.84mm 49-ball WLCSP with 0.4mm pitch
  • Flexible serial peripherals and ultra-low power ADC
  • USB host and device
  • Peripheral Event System and SleepWalking
  • Atmel ultra-low power picoPower® technology
  • 64-pin QFP and QFN package options.

In order to maintain energy efficiency, many smart, connected devices use a sensor hub to aggregate and manage the sensors in the device, converting the information into usable data to improve power efficiency and performance. The new SAM G55 series gives designers the option to determine how much SRAM they will require to retain in sleep mode in order to achieve lower and better power efficiency for their designs by utilizing SRAM power banking.

“Designers are looking for simple-to-use solutions with an edge to help bring their differentiated products faster to market for both wearables and sensor hub management,” said Vince Murdica, Atmel Senior Director of Sensor Centric Systems. “Atmel’s new SAM G series delivers differentiation for these markets by offering ultra-low power, higher performance, more memory and smaller form factor, along with connectivity options on a single chip to fuel the innovation. Atmel’s expanded SAM G series builds on our portfolio of touch, security, connectivity and software solutions for this rapidly growing market.”

To accelerate the design, a SAM G55 Xplained Pro evaluation kit is currently available for the SAM G55 series. The ATSAMG55-XPRO evaluation board includes an embedded debugger, Atmel Studio integrated development platform and the Atmel Software Framework. The kit is also fully supported by third party partners IAR and Keil.

Interested in learning more? You can check out Atmel’s entire SAM G lineup here.

BeON Home smart lights outsmart burglars


There’s smart bulbs, then there’s out-smart bulbs.


Did you know that four burglaries occur every minute in the United States alone? That’s a startling one every 15 seconds. The good news is that most convicted burglars (90%) claim they want to avoid homes with alarm systems, saying that if they did encounter an alarm, they would abandon the attack. However, the bad news is that nearly two-thirds of homeowners fail to turn it on at all times.

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While there has been an influx of smart bulbs in recent years, none of them may be nearly as intelligent as a new lighting system from one Cambridge, Massachusetts-based startup. The BeON Burglar Deterrent was designed to give off the impression of a lived-in home while you’re away, thereby outsmarting would-be intruders.

For those who recall the 1990s blockbuster film Home Alone, Kevin McCallister — played by Macaulay Culkin — outwits a pair of criminals by creating a DIY home security system. During one scene, Kevin goes to great lengths to set up a fake Christmas party in order to deceive the “Wet Bandits” into thinking that the house is, in fact, occupied.

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Well, BeON Home is seeking to bottle some of that Kevin McCallister spirit inside their new system. The BeON Deterrent — which is fresh off a successful Kickstarter campaign — is hidden within several LED bulbs, each of which provide plenty of light throughout a home. As its creators note, you shouldn’t have to compromise on your lighting quality for security and safety. That’s why each bulb in the BeON Burglar Deterrent system emits 800 lumens of soft white LED light, which is equivalent to your typical 60W incandescent bulbs.

While the smart bulbs install just like ordinary lightbulbs, and work with your existing wall switches, an additional ’smart’ module enables a whole new level of intelligence. In particular, the system is equipped to learn your home lighting activity patterns, which are then replayed while away to convey to potential thieves that someone is still home. Upon leaving the house, simply set the system to “protect” mode to activate this automatic lighting sequence.

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“No system programming is required. Simply activate and be on your way. Most would-be burglars will continue on their way, but the more bold ones may check if a home is occupied by ringing the doorbell,” a company rep adds.

Embedded with an Atmel | SMART SAM G ARM Cortex-M4 MCU, BeON’s sound processing engine can detect the tone of a doorbell and will immediately trigger the lights on in sequence to simulate your active presence, thereby increasing its level of ‘smartness.’ (Think of it as a professional grade Home Alone contraption.) Aside from the ATSAMG53 based sound algorithm, BeON bulbs boast backup rechargeable batteries, ensuring its burglar prevention powers work even without power.

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Furthermore, just as the bulbs can listen to your doorbell, the BeON system can hear other in-home events like smoke and carbon monoxide alarms. As a result, if BeON lights detect an alarm, they will immediately turn on at full brightness to assist home dwellers escape safely.

Following its successful crowdfunding campaign, the team hopes to add other audible functionalities to the bulbs, too. Imagine if when a burglar rings the doorbell, just before the first light comes on, a dog barks? Then, if the aspiring intruder continues, another light is triggered and immediately followed by the sound of a shotgun cocking? As with any Atmel | SMART MCU-driven innovation, the possibilities are endless!

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Not only is the system easy to use, but it’s simple to set up as well! So much so that the smart burglar deterrent can literally be configured and operated with a single finger. Each module is outfitted with a BLE module, which allows the system’s mesh network to extend the range of the bulb network throughout a house.

Looking to channel your inner Kevin McCallister and defend your home while away? Learn more about this bright idea by visiting their official page here. Full production is expected to get underway next spring, while shipping should begin this summer.

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Atmel expands metering platform for advanced smart energy apps

Atmel has expanded its Atmel | SMART portfolio of energy metering products with the recent introduction of the SAM4C32 dual-core secure MCU, along with the SAM4CMS32 and SAM4CMP32 for residential, commercial and industrial metering applications. The new system-on-chip (SoC) solutions have 2MB of cache-enabled dual-bank flash, are pin-pin compatible with existing 512KB and 1MB devices in the portfolio, and allow unparalleled scalability and design-reuse for next-generation smart metering platforms.

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The SAM4Cx series is built on a dual-core 32-bit ARM Cortex-M4 architecture with flexible firmware metrology capability up to a class 0.2 accuracy designed to meet WELMEC requirements for the separation of legal metrology, applications and communications. All devices include advanced security features, low-power real-time clock and LCD driver, and multiple serial interfaces resulting in a best-in-class level of integration, performance and lower bill of material (BOM) cost.

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“As the rate of smart meter deployments continue to rise in several European and Asian regions, our customers demand an unprecedented level of integration and scalability to maximize their R&D investment and to address multiple utility markets more quickly at lower cost points,” explained Kourosh Boutorabi, Atmel’s Senior Director of Smart Metering. “We are committed to offering next-generation smart metering system architects a broad portfolio of solutions based on the same core platform architecture, software and tools.”

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As we’ve previously discussed on Bits & Pieces, the Atmel | SMART SAM4Cx is a comprehensive smart energy platform designed specifically for grid communications, electricity, gas and water metering systems, and energy measurement applications.

Key features of the SAM4CMS32 and SAM4CMP32 include:

  • Application / Master Core
    • ARM Cortex-M4 running at up to 120MHz
    • Memory Protection Unit (MPU)
    • DSP Instruction
    • Thumb®-2 instruction set
    • Instruction and Data Cache Controller with 2 Kbytes Cache Memory
    • 2Mbytes of flash, 256Kbytes of SRAM, 8Kbytes of ROM
  • Coprocessor (provides ability to separate application, communication or metrology functions)
    • ARM Cortex-M4F
    • IEEE 754 Compliant, Single precision Floating-Point Unit (FPU)
    • DSP Instruction
    • Thumb-2 instruction set
    • Instruction and Data Cache Controller with 2 Kbytes Cache Memory
    • 32K+16K bytes of SRAM
  • Symmetrical/Asynchronous Dual Core Architecture
    • Interrupt-based Inter-processor Communication
    • Asynchronous Clocking
    • One Interrupt Controller (NVIC) for each core
    • Each Peripheral IRQs routed to each NVIC Inputs
  • Cryptography
    • High performance AES 128 to 256 with various modes (GCM, CBC, ECB, CFB, CBC-MAC, CTR)
    • TRNG (up to 38 Mbit/s stream, with tested Diehard and FIPS)
    • Public Key Crypto accelerator and associated ROM library for RSA, ECC, DSA, ECDSA
    • Integrity Check Module (ICM) based on Secure Hash Algorithm (SHA1, SHA224, SHA256), DMA assisted
  • Safety
    • Two (ATSAM4CMS32) / one (ATSAM4CMP32) physical Anti-Tamper Detection I/Os with Time Stamping and Immediate Clear of General Backup Registers
    • Security Bit for Device Protection from JTAG Accesses
  • Shared System Controller
    • Embedded Core and LCD Voltage Regulator for single supply operation
    • Power-on-Reset (POR), Brownout Detector (BOD) and Dual Watchdog for safe operation
    • Ultra-low-power Backup mode (< 0.5 µA Typical @ 25°C)
    • Optional 3 to 20 MHz quartz or ceramic resonator oscillators with clock failure detection
    • Ultra-low-power 32.768 kHz crystal oscillator for RTC with frequency monitoring
    • High-precision 4/8/12 MHz factory-trimmed internal RC oscillator with on-the-fly trimming capability
    • One high-frequency PLL up to 240 MHz, one 8 MHz PLL with internal 32 kHz input
    • Low-power slow clock internal RC oscillator as permanent clock
    • Power Supply
    • Clock
    • Ultra-low-power RTC with Gregorian and Persian Calendar, Waveform Generation and Clock Calibration
    • Up to 23 Peripheral DMA (PDC) Channels
  • Shared Peripherals
    • One Segmented LCD Controller
      • Display capacity of 38 segments and 6 common terminals
      • Software-selectable LCD output voltage (Contrast)
      • Can be used in Backup mode
    • Four USARTs (ATSAM4CMS32) or three USARTs (ATSAM4CMP32) with ISO7816, IrDA®, RS-485, SPI and Manchester Mode /
    • Two 2-wire UARTs
    • Up to two 400 kHz Master/Slave and Multi-Master Two-wire Interfaces (I2C compatible)
    • Up to five Serial Peripheral Interfaces (SPI)
    • Two 3-channel 16-bit Timer/Counters with Capture, Waveform, Compare and PWM modes
    • Quadrature Decoder Logic and 2-bit Gray Up/Down Counter for Stepper Motor
    • 3-channel 16-bit Pulse Width Modulator
    • 32-bit Real-time Timer
  • Energy Metering Analog-Front-End Module
    • Works with Atmel’s MCU Metrology library
    • Compliant with Class 0.2 standards (ANSI C12.20-2002 and IEC 62053-22)
    • Four Sigma-Delta ADC measurement channels, 20-bit resolution, 102 dB dynamic range
  • Analog Conversion Block
    • 6-channel, 500 kS/s, Low-power, 10-bit SAR ADC with Digital averager providing 12-bit resolution at 30 kS/s
    • Software Controlled On-chip Reference ranging from 1.6V to 3.4V
    • Temperature Sensor and Backup Battery Voltage Measurement Channel
  • I/O
    • Up to 57 I/O lines (ATSAM4CMS32) or up to 52 I/O lines (ATSAM4CMP32) with External Interrupt Capability (edge or level sensitivity), Schmitt Trigger, Internal Pull-up/pull-down, Debouncing, Glitch Filtering and On-die Series Resistor Termination
  • Package
    • 100-lead LQFP, 14 x 14 mm, pitch 0.5 mm

Learn more about the newest SAM4C32 MCUs here.

Baskin-Robbins only has 31 flavors, Atmel has 505

Actually these days even Baskin-Robbins has more, but not 505 like Atmel. That’s a lot. While some are AVR, both 8-bit and 32-bit, others are various flavors of ARM (all 32-bit) ranging from older parts like the ARM9 to various flavors of Cortex ranging from the M0 (tiny microcontroller with no pipeline or cache) up to A5. Of course, the ARM product line goes all the way up to 64-bit Cortex-A57 and so on — but they are not in any sense of the word microcontrollers and are really only used in SoCs and not standalone products.

But with 505 choices, how do you pick one? Fortunately, Atmel has made it easy for you to navigate the various flavors. With the help of the company’s MCU product finder, you now have the ability to input your hard constraints, while the tool will narrow down the choices. For example, if you want your microcontroller to have at least 64 Kbytes of flash, then there are only 257 out of the 505 that will suit your needs. For each parameter, users can set minimums and maximums — except for the yes/no choices.

When it comes to the selection process, there are several things that you can constrain:

  • Flash memory (0 to 2Mbytes)
  • Pin count (6 to 324)
  • Operating frequency (1 to 536MHz)
  • CPU architecture (pick from 8-bit AVR, 32-bit AVR, ARM 926 and 920, ARM Cortex M0, M3, M4, A5)
  • SRAM (30 bytes to 256 Kbytes)
  • EEPROM (none to 8 Kbytes)
  • Max I/O pins (4 to 160)
  • picoPower (yes or no)
  • Operating voltage (various ranges from 0.7V to 6V)
  • Operating temperature (various from -20oC to 150oC)
  • Number of touch channels (none to 256)
  • Number of timers (1 to 10)
  • Watchdog (yes or no)
  • 32KHz real time clock (yes or no)
  • Analog comparators (0 to 8)
  • Temperature sensor (yes or no)
  • ADC resolution (8 to 16 bits)
  • ADC channels (2 to 28)
  • DAC channels (0 to 4)
  • UARTs (0 to 8)
  • SPI (1 to 12)
  • TWI (aka I2C) interface (none to 6)
  • USB interface (none, device only, host+OTG, host and device)
  • PWM channels (0 to 36)
  • Ethernet interfaces (none to 2)
  • CAN interfaces (none to 2)

Wow, that’s a lot of options! But after a couple of dozen selections, you can narrow down your choice to something manageable. Here’s how the interface will appear:

Say for instance, I wanted to pick a microcontroller, an ARM Cortex of some flavor. Already choices are down to 189. I want 32K to 128K of flash (now down to 73 choices). I want it to run at an operating frequency of at least 64 MHz (now down to 10). I want 4K of SRAM (turns out all 10 choices already have that much). I need 4 timers. I am now down to 2 choices:

These two choices are the ATSAM3S1C and the ATSAM3S2C — both ARM Cortex-M3s. The first has 64K of flash and the second 128K. I can click on the little PDF icon and access a full datasheet for these microprocessors. If I don’t like the choices and I have some flexibility on specs, then obviously I can go back and play with the parameters to get some new options.

I can click on the “S” to order samples. However, in order to do this, you must already have an Atmel account. Or, with just another click on the shopping cart icon, I can obtain a list of distributors throughout various geographic regions, where I can actually place an order. It even tells me how many each of them have in stock!

For those of you ready to start searching, you can find the Atmel Microcontrollers Selector here.

This post has been republished with permission from SemiWiki.com, where Paul McLellan is a featured blogger. It first appeared there on March 2, 2014.

Atmel’s SAM4L ARM Cortex-M4 MCU saves power with FreeRTOS tick suppression

FreeRTOS can best be described as a popular real-time operating system for embedded devices, including Atmel’s SAM4L ARM Cortex-M4 MCU (microcontroller). The real-time operating system is succinct, as it consists of three or four C files, and is written primarily in the same language.

So why use an RTOS? Well, a real-time operating system for embedded devices offers a wide variety of benefits, including an optimized design with cleaner interfaces, the ability to reuse code and the opportunity to benefit from low-power operation.

Applications coded to take advantage of an RTOS are designated as a set of of autonomous, communicating threads of execution. Specifically, in FreeRTOS each thread of execution is known as a task, with each typically spending varying degrees of time waiting for an event.

As Richard Barry of FreeRTOS explains, a task may have to wait for an interrupt, a time period to expire, or a message from another task.

“In FreeRTOS a task that is waiting for something to happen is said to be in the blocked state. An RTOS scheduler will not run a task that is in the blocked state. When all the tasks that were created by the application are in the blocked state the RTOS scheduler will run a task called the idle task, which is created by the RTOS itself,” Barry wrote in a recent blog post published on EE Times Embedded.

“An RTOS therefore provides a very convenient and automatic way of knowing when the application is idle, and therefore when the microcontroller on which the application is running can be placed into a low-power state.”

Indeed, FreeRTOS allows an app writer to add their own into the idle task via the definition of an idle task callback or hook function. It is therefore quite common to reduce the power consumed by the microcontroller on which FreeRTOS is running by exploiting the idle task callback to switch the microcontroller into a low power state.

However, the resulting power saving achieved by the above-mentioned method is limited if the RTOS requires a periodic exit of the low power state to process tick interrupts (periodic interrupts used by an RTOS to track time). Meaning, any energy savings will be outweighed if the frequency of the tick interrupt is excessive – for all but the lightest power saving modes.

Enter the FreeRTOS tickless idle mode, which halts (or suppresses) the periodic tick interrupt when the idle task is executing, subsequently making a correcting adjustment to the time maintained by the RTOS when the tick interrupt is restarted. This allows the microcontroller to remain in a deep power saving state until an interrupt occurs or the RTOS kernel transitions a task out of the blocked state.

“There is a run-time overhead associated with suppressing the tick interrupt: the peripheral used to generate the periodic tick must be reprogrammed before entering the low-power state, and again when exiting the low power state,” said Barry.

“For this reason, and to ensure correct processor time sharing between tasks of equal priority, the tick interrupt is not suppressed unless all the application tasks are in the blocked state.”

The tick suppression feature supported by FreeRTOS can perhaps be best illustrated by Atmel’s SAM4L ARM Cortex-M4 microcontroller, which is specifically designed for low power applications.

As you can see in the image below, the SAM4L evaluation kit (SAM4L-EK) includes a board monitor that displays the amount of current consumed by the microcontroller as it executes applications.

This particular image is a photograph of the board monitor display captured when the microcontroller was executing a simple FreeRTOS demo with the optional tick suppression feature enabled – clearly spending the majority of its time in the special retention low power mode of the SAM4L.

“The current readings taken when in retention mode resulted in the flat horizontal line visible along the bottom of the graph in the photograph. Every 500 and 500 + 20 milliseconds an application task briefly left the blocked state to perform a trivial piece of processing,” Barry noted.

“The current readings taken when an application task was executing resulted in the two small dots that appear four times on the graph above (the measurement resolution and screen resolution make the dots appear almost as one elongated dot). As four execution instances are visible on the graph it can be seen that the graph in the photograph covers a two second period.”

Additional information about Atmel’s SAM4L can be found here, while key data pertaining to FreeRTOS and its tick suppression feature is available here.