Taking apart a vintage Symphonic SL-149 record player

So audio guru Steve Williams sent me a bunch of pictures of a portable phonograph that he just bought. He collects these old cheap units. It’s kind of like collecting beetles, they are ubiquitous and dumb, but you have to admire their diversity. So Steve has an inordinate fondness for 1960’s vintage portable record players.

The Symphonic SL-149 record player ready for business. This is the kind of unit we used to put an old Pink Pearl eraser on the tone arm so it would stay in the groove.

He didn’t say where he got it, but eBay is full of such treasures.

Here is the Symphonic SL-149 record player in all its glory.

Steve wrote us a mock note, acting like he was a young kid that could not understand something this simple.

“Can any or all of you help me to understand the complex subtleties of this device? Note the schematic includes 5 resistors including a variable one, plus 3 capacitors, a little heat sink diode thingie, a motor, a switch, a tube, a transformer, a speaker, and this funny thing that creates electricity when bent back and forth via perturbations in a flat disc rotating beneath the arm thingie that the little crystal generator is located at the end of. Said disc being rotated via the motor through a rubber wheel connected to the table the disc rests on…”

“It’s all too simple to do anything. There must be some magic involved. Where is the software, what is the storage media, what is the underlying code? Where is the D to A converter for that matter?”

Here is the schematic that Steve Williams was marveling over. I know someone will be doing a Spice run on it now.

Of course, why buy this old precious stuff if you don’t immediately take it apart? Here are the guts of the unit. This is the kind of things my pals bring up with a Variac variable transformer, to try and condition that old paper capacitor. Usually it is these caps that go bad, putting a huge 120Hz ripple in the power supply, which you hear as a horrible hum in the sound.

Old phonographs are much more interesting inside, where there are mechanical motors and gizmos and tubes and such. Hand wiring—nice.

My pal Eric Shlaepfer restored an old Clough-Brengle oscillograph. Eric doesn’t just replace those old dried-out capacitors with new ones. He takes apart the old capacitors and puts a new one inside, so the restored ocsillograph still looks vintage. Bravo.

This is Schlaepfer’s trick to put a modern film capacitor into the guts of a dried out paper capacitor shell.

And in case you want to see Steve’s record player working, here is a YouTube video of a similar one playing a record.

[Update:] I sent this post to audio guru Steve Williams and he sent back a nice note:

“Thanks for the write up. Only minor correction is that the video on my YouTube channel is of the same player not a similar one. Yes, the cap is weak but the hum is only semi atrocious. Didn’t replace it yet. Put in a very similar NOS Crystal cartridge I had. The album is my very first LP. I sent the mass email and initially only Ron Quan responded. -“

‘It’s a very efficient circuit by using the tube to drop 25 volts AC for the motor winding. The crystal cartridge could deliver at least 0.5 volt AC into the grid of the 25L6. As I recall, these phonographs could play very loud. Of course, the tracking force was in the order of 5 grams or more. Ron’

“Of course Ron meant that the motor drops the other 90 some odd volts leaving 25 for the 25L6 filament in series. (Which AFAIK is  _not_  the same as a 6L6 with a different filament voltage.) –Steve”

 

All tiny AVR parts in a spreadsheet

I just made a spreadsheet of all the tinyAVR parts. All my pals love the MCU selector guide, but I have a lot of analog dinosaur buddies that prefer a spreadsheet to a web-based interface. You can sort the data and this spreadsheet has the filter box on the columns, so you can sort out things you care about and exclude the things you don’t. The spreadsheet fits on a 24-inch display, and you can print it out on a single B-sized sheet and use it as an infographic.

This screenshot shows how all the tinyAVR parts will fit on one 11×17 ledger-sized or B-sized sheet of paper.

I started with an Excel dump of the selector guide after adding every single parameter to the search. I then took all the tinyAVR parts, and rearranged the columns, throwing out the irrelevant ones. I also combined the automotive parts with the basic parts. That added two columns for automotive temp and automotive Vcc range. Adding 2 columns to remove 13 rows seemed like a good deal. The part name links to the product page on our website.

I made a column for each package. That took a long time. Semiconductor companies think of a part as the silicon die, with the package being almost irrelevant. We systems folk know the package might be the most important thing. I tried to put the smaller packages on the left, with those big ol’ DIP (dual-inline plastic) parts on the right side. There is a second sheet in the spreadsheet that shows all the parts by number and there I put the package size, in mm. In both sheets, the package name links to the definition page on our website.

The second sheet of the spreadsheet shows all the tinyAVR parts by number. I put the exact package size on this page.

Besides the packages and package size, I also spent a long time getting pricing. My buddy Wayne Yamaguchi requested this, and he is absolutely right, price is the most important spec of any part, and I hate when it takes 5 clicks to find it. These prices are a bit sketchy. All I did was click on the “Buy” link and select a handful of parts from each family, and then looked at the Digi-Key price, in 1000s. I put in the highest and lowest of the few I selected, but this is by no means scientific or dispositive, as the lawyers would say. What I should do is put the price in the “Package” column, so you know what the package is and what price we charge, but many parts are in the same package but have two Vcc ranges, so there is no unique way to encode this and keep the spreadsheet on one printable page. Maybe I can blow out the second page to show every orderable part number and its price and specs. Always time to do it over, never time to do it right.

The major thing I want to add is the OrCAD 9.2 footprint name for the packages. I am afraid to do this now, since we have all been burned by narrow-DIP/wide-DIP and narrow -SOIC/wide-SOIC and what pin numbering to use on SOT parts, so that will have to wait for next time. If anyone has a proven definitive list of the OrCAD footprints, please let me know. paul.rako[yeah, the at sign]atmel.com

You can highlight all the parts and use the “Data>Sort” function to order them any way you want. I did it by Flash memory size and part name. You can also use the little filter boxes on each column to include or exclude, or even put in a logical range with equal or less than or all the other things. Its not exactly grep or regular expressions, but it can get the job done helping you to find the right part.

Excel filter boxes let you select just the parameters you care about.

I am told this spreadsheet works OK in Open Office/Libre. My pal Dave asked that any columns that are filtered be lit up red, but that takes a macro, and the VB macro may not work in Open Office, we are checking for that. Meanwhile, check there are 36 part families or that the little filter box does not have 3 pixels different to show the filter is on.

When you have filtered a column, it is almost impossible to tell, since the only indication is the icon makes this 3-pixel change.

Weasel weasel, CYA CYA, legal boilerplate—this is a hobby job, not an official Atmel document. If the selector guide had it wrong, it is wrong here too. I made my own mistakes too. And I already told you the pricing and the tiny1634 stuff was dicey. What I am hoping is that I can get some community support where you point out the errors, and tell me what to add. paul.rako[yeah, the at sign]atmel.com I also ask that you send this URL link to your pals, instead of just emailing the spreadsheet. That way the bosses will see you like this, and I can have the time to keep working on it.

If Hans Camenzind, the inventor of the 555 timer chip was still alive, he might have a copy of the tinyAVR spreadsheet up on his office wall. I miss Hans, at least he came to my Analog Aficionados party one year, before we lost him to the Grim Reaper.

 

Medical tech surging with the Internet of Things

Medical devices are proliferating at a bewildering pace. My pal Frank Fowler sent this YouTube video of how you can use your smartphone to take an EKG or monitor your vitals. Of course, we engineers know that the phone is just a passive display, the real action is in the sensors, signal conditioning and wireless tech used to get the signals to the cloud. It’s an embedded world and consumers are going to be blown away by all the useful products that we engineers will be bringing them. In addition to the pillars of microcontrollers and wireless, Atmel is committed to bringing security chips to market too. For medical applications like this, security is more than a nice feature; it may be a regulatory requirement to insure your data remains private.

The video demonstrates a little misunderstanding that the iPhone is in any way central to this. All it is doing is displaying data. It is the sensors and signal conditioning that are the real revolution. The late Jim Williams designed a scale so accurate it can measure your heartbeat (Fig 11). So a buddy of his quit Apple and did a startup where you put a pad under your mattress and it measures your heart-rate while you sleep. Once the embedded system gets the data, you can send it wirelessly to your TV or your phone or to the cloud cloud cloud. To think the iPhone is central to this is like thinking the box on your wall is the central part of making a TV program.

What is fascinating to me is how things just seem to work out. We will need storage for all this, and how convenient that Hitachi Data Systems, where my buddy Fowler used to work, makes boxes full of spinners that will hold all this information. In fact, when considering the cloud cloud cloud, it occurred to me that the suitable analogy is electricity production. Data is good. Electricity is good. We used to have a little generator in the basement. We used to have a little server in the basement. That was a pain, so we moved all the generators and servers to one central location. All that the cloud cloud cloud is doing is combining all the little generators into one big one, something the electricity people did 100 years ago. Soon the data people will go back to the mainframe, since why do all this dynamic load balancing across 5000 machines when you can do it across 50? And this is the great brilliant progress of our modern age. Indeed the cloud cloud cloud is almost irrelevant to the user. I don’t care if Dreamhost has one machine or a million, as long as they send out the pages quickly. The cloud cloud cloud helps that to a point, but it also lessens reliability and adds overhead. We live in wondrous times.

While stuffing blades into a web server and dynamically balancing them is neat, of far more interest to me is the embedded world. Here there is a delightful design challenge, getting low power to balance with high performance. My programmer pal John Haggis was showing off his Omron blood pressure monitor the other day;

This Omron blood pressure monitor can take your vitals in less than a minute.

The next task will be to connect the monitor to you phone via Bluetooth or Wi-fi. Now your phone can send the data up to the internet where it can be stored, analyzed, and shared with your doctor. You can envision the network effects taking hold, where your blood pressure results will dynamically modify the shopping list at your grocery store. If your blood pressure is low enough, maybe you can have some salty snacks this week. Keep it low and you might get a rebate on your health or life insurance. If your blood pressure shoots up the IoT can correlate it to that restaurant where you had a meal that caused it.

 

Electronic component art sculptures

My pal Phil Sittner sent a link to this picture of a rock band made out of electronic components. You have to love the title: L.E.D. Zeppelin.

Apparently that picture inspired this mom to make her own art:

All this creativity is near and dear to my heart, since my dear departed analog pal Jim Williams was also a lover of electronic art. One nice feature of Jim’s art was that it often functioned as a real working circuit as well as being a free-form sculpture.

So if you have an artistic bent, think about soldering up some items from your junk box to make something beautiful and fascinating.

This smart umbrella tracks air pollution

What if your umbrella could help protect the world from air pollution while it protected you from rain? Copenhagen Institute of Interaction Design students Saurabh Datta, Akarsh Sanghi, and Simon Herzog recently debuted an umbrella capable of just that. Appropriately dubbed “Sensing Umbrella,” the smart device has the ability to collect air pollution data during a nice stroll through the park or en route to work.

In order to bring the project to life, the team collaborated with Arduino Co-Founder Massimo Banzi. Created in conjunction with Giorgio Olivero of ToDo Design, the smart umbrella equipped with an Arduino Yún (ATmega32u4 MCU) is tasked with measuring local carbon monoxide and nitrogen dioxide pollution levels.

According to Co.Design’s Carey Dunne, the umbrella then visualizes this data in real-time through a sparkling LED light display on its surface. “Firefly-like lights change their color and rhythm in response to local pollution levels, spreading awareness of the air quality to city dwellers,” Dunne explained.

“This timestamped and geolocated data gets uploaded to the Cloud–to pollution databases–to be analyzed.”

With the emergence of the latest and greatest ’smart’ designs, this is rare piece of tech that aspires to do greater social good than just quantify and improve our individual selves. “As designers, we wanted to embrace this ongoing revolution of ‘The Internet of Things’ with a clear mission: to actively care for the people who use these connected devices,” Maker Akarsh Sanghi tells Co.Design.

In the long term, the Institute of Interaction Design students hope to generate local maps of air pollution hosted on an openly available web-based platform. “This project is entirely based on open-source hardware and software,” Sanghi says. Though the team doesn’t plan to monetize the project or open a company based on the concept, they do hope to create a worldwide event, or movement, in which crowdsourcing data via umbrella turns every person in society into a node in a larger network.

Interested in learning more? You can check out the Sensing Umbrella’s official page here or watch it in action below.

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.

Does your smartphone’s touchscreen support moisture touch?

Recently, I met an Atmel maXTouch customer whose smartphone brand is well recognized by consumers in West and East Africa, competing against smartphones made by global brands like Samsung and Nokia. When the customer selected our touchscreen controller for their smartphone product, they needed two features that were very important for African consumers: robust moisture performance and strong noise immunity. This is hardly a surprise as many African countries have unreliable power supplies, and surge protection is important for electronic devices; additionally, the warm climates in most African countries make robust moisture performance a basic requirement for touchscreen controllers to handle sweaty fingers, palms and faces. When the touchscreen controller has trouble in combating charger noise or moisture presence on the touchscreen, a symptom called “ghost touch” would occur – in other words, when the touchscreen automatically triggers a false touch without the presence of a finger contact at that specific location.

With Adaptive Sensing technology, Atmel’s maXTouch T-series scans the touchscreen of a smartphone using both mutual-capacitance and self-capacitance sensing.

Mutual-capacitance enables true multi-finger touch operations, such as multi-finger gestures and rotations used in gaming apps. However, self-capacitance sensing is much less sensitive to the presence of moisture or water droplets than mutual-capacitance. Atmel’s Adaptive Sensing technology combines the analog signals of both self-capacitance and mutual-capacitance, allowing the embedded maXTouch microcontroller to intelligently determine moisture presence through obvious differences in both measurement deltas for corresponding touch locations. As seen in the example below, here a maXTouch device combines both set of signals to eliminate false touch (a.k.a. ghost touch) typically associated with the presence of moisture on a touchscreen.

I should point out that a smartphone with an excellent water-resistant rating does NOT necessarily mean that it has a robust moisture performance for its touchscreen. Here is a tidbit of consumer feedback on a premium smartphone with IP58 rating:

In comparison, the OEM customer designs smartphones for African consumers that can offer excellent touch performance with the presence of moisture, thanks to our maXTouch T-series. The maXTouch mXT640T series of touchscreen controllers dynamically switches into a Self-Capacitance based single-touch mode when touches are detected in the presence of significant water. This meaning, the normal touch functionality of a mXT640T touchscreen will be maintained for as long as possible before eventually switching to a single touch operation to maintain reliable operation and prevent false touch conditions. The picture below illustrates how we set the bar for superior water/moisture performance in the market:

All in all, a touchscreen powered by Atmel’s maXTouch T-series controllers can support true multi-finger operations with the presence of moisture. Even in a rainy condition where water falls down to your smartphone, the system dynamically maintains reliable touch operations and prevents false touches, so that when you press a speed-dial for Uber in the rain, your phone will not innocently call your ex-girlfriend instead.

 

Accelerate your evaluation of Atmel 802.15.4 wireless solutions from your desktop

You have probably come across this scenario before: Management or the marketing department approaches you asking you to add wireless functionality to an existing product, or to develop a new product that needs to be able to support a wireless link. Today, there are many wireless technologies and options to consider.

It is also quite possible that marketing has already made part of that decision for you.

The marketing requirement may stipulate that you use Wi-Fi, Zigbee, 6lowpan or Bluetooth low energy (BLE). Or, maybe marketing has no idea what is required, and just tells you to implement a wireless link!

So, after a number of meetings and conference calls, you decide to use a solution that is based upon 802.15.4. This could include Zigbee, 6lowpan, Wireless HART, ISA100.11a, Openwsn, Lwmesh, among many other wireless stack solutions that all require an 802.15.4 compliant transceiver.

At this point you would need to decide if your solution, or the protocol you’ve selected, will operate in the 2.4 GHz band or in a SubGhz band. There are times when you will need to do some experimentation or RF performance evaluations to determine which RF band to use in your particular situation.

When evaluating Atmel 802.15.4 wireless solutions, the first tool you should turn to is Wireless Composer. Provided as an extension to Atmel Studio 6.x, the Wireless Composer is a free tool. In order to make it simple, each of the current Atmel 802.15.4 evaluation kits/platforms comes with a Performance Analyzer firmware application pre programmed into the kit. Running on the evaluation kit, this Performance Analyzer firmware is designed to communicate with both the Atmel Studio and Wireless Composer extension.

Some of the capabilities of Wireless Composer include:

• Energy Scan: Scan selected or all available 802.15.4 channels

• PER (Packet Error Rate) Testing: Transmit and receive 1000’s of frames at a specific TX power level and RF channel and then review the results for errors (dropped bits/frames) while also evaluating throughput metrics.

• CW Test Modes: Place a device in a Continuous test mode to monitor emissions with a spectrum analyzer or other RF test equipment

• Antenna Evaluation: Provide a Large Digital Display to allow testing antenna radiation pattern’s at distances of up to around 3 meters from the device connected to the laptop PC.

• Range Testing: Gather and log range data generated from a  wireless link set up between two nodes — this data includes RSSI (ED signal strength) and LQI (signal quality) from both sides of the RF link.

Here are a few additional example screen captures, available from within Wireless Composer.

Energy Detection Scan Mode:

Screenshot of Wireless Composer, an extension of Atmel Studio 6.x – Energy Detection Scan

Have you ever wanted to set up some RF tests and wanted to know if there were other transmissions already taking place on the channel you intended to test on ?  Maybe your colleagues  are performing tests in another section of the lab or building, or maybe at home you have Wi-Fi or Bluetooth or home automation devices operating in close proximity to where you want to run some experiments.  The ED scan mode, as shown here, allows you to get a quick glimpse of what RF activity is happening around you. You can do a one time scan or you can configure the test to continuously scan one or all channels and repeat this until you stop the test.

PER Test:

A common RF test to perform on a packet based wireless communication system is a PER (Packet Error Rate) test.

This test mode allows you to configure operation on a particular channel, at a specific TX power level, using a selected antenna option. You are then provided the ability to set the number of bytes to send in a transmitted frame, and to set how many frames you are going to send during the test. All of these parameters are configured in the left hand Transceiver Properties Pane, as shown in the capture below. Once the test is performed, the right hand window provides data regarding the results of the test.

This can be useful for confirming RX sensitivity parameters, and data throughput characteristics under different conditions. Here is an example of sending 1000 frames and achieving zero errors using a frame length of 20 bytes.

Screenshot of Wireless Composer, an extension to Atmel Studio 6.2 – Packet Error Rate test mode

 

Continuous Transmission Test Mode:

If you have attempted to develop a wireless RF product before, you know that a considerable amount of time will be spent performing regulatory pre – scan certification testing. This typically involves configuring your device to transmit a continuous wave RF emission on a particular RF channel using a specified amount of Transmit power. The RF emissions are monitored using a spectrum analyzer or other RF test equipment. To help save time and provide a useful tool, Wireless Composer provides a Continuous Transmission Tab that allows selection of a few different tests of this type.

In the example shown below, an unmodulated CW test transmission has been started on channel 16 using a TX power level of +4dBm. These are no results reported here, because all measurement results would come from observing the RF test equipment that monitors the RF emissions.

Screenshot of Wireless Composer, an extension to Atmel Studio 6.2 – Continuous Wave test mode

 

Antenna Evaluation Range Test Numerical Display:

For any wireless product, the antenna is one of the most important sections of the design. A great radio with a poor antenna results in poor product performance, while a mediocre radio with a great antenna can end up with very good performance. So, one of the tasks for any wireless product developer is to understand the characteristics and performance of his antenna design. This may be some type of on board antenna like a ceramic chip antenna, or a pcb trace antenna, or it just may be connecting an external antenna to an RF connector mounted on the product’s pcb. Many on board antenna designs are shortened quite a bit to reduce the footprint or space required by the antenna. This usually will affect the performance of the antenna in a negative way, or at a minimum create directivity to the antenna’s radiation pattern. A nice capability of Wireless Composer is the ability to allow you  to place the device connected to the PC, running Wireless Composer, on a table or tripod at a specific height above the floor in an open indoor or outdoor area. Then, in the range test tab within Wireless Composer, select “Numerical “ as the display mode. This will then display a screen as shown below.

One would then take a battery operated mobile node about three meters away from the PC display and watch the values being displayed for ED/RSSI and LQI change as you rotate or change the orientation of the antenna with respect to the unit at the other end of the link. This display shows the LQI and ED/RSSI values at both ends of the link and can be used to examine any changes in antenna pattern, as the device orientation is changed. Knowing what orientation provides the best signal levels will later help you understand how to position the unit when mounting it at its final location. You will also acquire information on how to set up additional range tests where you could be up to one mile away, and all you have is a blinking led to indicate whether or not you still have communications with the unit under test.

Screenshot of Wireless Composer, an extension to Atmel Studio 6.2 – Range Test Numerical Display

 

Range Test Log With Multiple Markers (Push Button Marker Recording):

Wireless Composer also has a range test mode for logging signal level and quality to a PC display or to an Excel file, as shown in the screen capture below.

When two paired devices are configured in this range test mode, the unit connected to the PC will periodically (about every two seconds to conserve battery life) send a beacon type frame to the mobile unit, at which point the mobile unit will send back a reply to the logging device. This activity can also be seen in the screen capture below.

The LQI and ED (average RSSI) levels for each side of the wireless link are recorded with a time stamp to an Excel file.

Have you ever tried to do an RF range test by yourself? If you have, then you know that it sometimes can be difficult to set up a test, such that you can leave one node at a fixed location and take the other battery operated mobile unit to various locations where you want to gather signal level and link quality information.

This is especially true when your simple wireless device lacks any type of user interface, or display attached to it, as in the case of a wireless sensor, or an simple evaluation board. This becomes even more difficult if you are doing LOS (line of sight) measurements outdoors. The performance analyzer app only assumes you have access to two IO pins — one is typically an input for a push button or jumper, while the other is an output for an LED.

Outdoor LOS measurements may allow you to achieve distances of hundreds of meters, as well as one or more miles in the SubGhz RF bands.

To make this measurement task a lot easier, the performance analyzer app has the ability to enable you to press a button on the battery operated portable unit that you have in your hand, and have this RF device send an RF frame back to the unit connected to the PC that is doing the logging; as a result, that marker frame is recorded into the log, allowing you to place marker indicators for time and place in the log file. This will enable you to determine where you have been when you return to review the log data.

For instance, you could press the button once while at a specific location in room A, and then press it twice in for a location in room B. Or, if you are outdoors you could press the button and insert markers at various distances as you move away from the logging unit. Then, all you would have to write on your notepad while doing the test would be the name of your location (or the distance at which you were away from the logging unit) and the number of times you pressed the button at that location.

Upon your return to examine the recorded log, you’ll have all of the necessary information to understand the recorded results, including where in space and time the measurements were made.

See the example below:

Screenshot of Wireless Composer, an extension to Atmel Studio 6.2 – – Recorded Logs

 

For each of the supported wireless platforms, Atmel Studio contains complete example projects with source files for the performance analyzer application. When you are finished making measurements on an Atmel evaluation board that you used to help make device selection or RF band selection decisions, you can then use this same application with possibly some minor modifications to support your own final hardware design with regards to the IO assignments for a push button or led. This performance analyzer application along with Wireless Composer have proven to be very useful when performing tests on first prototype boards, and even for use in performing FCC or other governmental regulation pre-scan testing.

Interested in learning more? You can access Wireless Composer here and Atmel Studio here.

 

 

Please explain to Grandma: What’s the SAM D20 Xplained Dev Board?

My side of the family is very small. I have two parents and a sister, and it stops just about there. My girlfriend’s family, on the other hand, is quite the opposite. A large family means regular family events, and after close to ten years, I still haven’t met everyone. This is just one of those occasions, where I smile, and pretend not to be terrified.

There are a few people walking around the room, but the three mains congregation points are in front of the huge fireplace where apparently someone has attempted to put in a small tree, and just push it in as the end burns away. The table is full of food, and quite a few people are nibbling on delicious snacks. Then there is apparently a line of grandmothers at the back of the room. I hear my name spoken from this part of the room, and I turn around to see five grandmothers looking at me, as well as one or two unknown members of the family. I think I’m supposed to say something.

Excuse me?

– I said that you had just written a book.

Yes, indeed.

– What is it about? Asks one of the grandmothers. They all look at me.

We’ve all been there, a family reunion, where you suddenly become the center of attention. I am subjected to a two hundred kilowatt neon blue stare, the sort of look you get when you are asked the famous family questions; When are you going to get a haircut? When are you going to get a job? And when are you going to come over and see the neighbors because they have this fantastic son/daughter who is single and has just had this promotion at work! I think I’m losing weight just being subjected to this look. Here we go. It is a technical book—about ARM processors.

– Oh, that’s nice!

That one phrase says it all. I start counting under my breath. Two… Three…

– And, um, what exactly is an ARM processor?

I start to explain that it is a type of processor, the “brains” if you will of modern machines. A few weeks ago, I was asked to explain the IoT to someone, and that person is here, practically jumping up and down in excitement.

– Show them the Internet thingy!

Very quietly, from the privacy of my own head, I sigh. Internet of Things, not the “Internet Thingy”. Please excuse me while I go and fetch it. I also take the opportunity to drink an ice-cold glass of water.

Atmel’s SAM D20 Xplained Development Board

On returning, I show them the board, an Atmel SAM D20 evaluation board that I used for my book. I explain that the SAM D20 is based on an ARM processor, using Atmel’s technology, and that the entire board is used as a prototyping device, capable of hundreds of applications, depending on your imagination. I also point out the SAM D20 itself; this little black thing here, the size of a thumbnail that is the processor…

– That isn’t a processor.

I come from a very technology-phobic family. My mother spent weeks looking for a microwave with a single button because she doesn’t want to have to enter any information at all, not even the amount of seconds. My father’s grasp of computers is fairly limited; when asked how much RAM he has, his answer is “Enough, I suppose”. It’s the same for every single component. He uses them because he doesn’t have a choice. He still has a telex machine in his office. It’s almost a miracle I got into technology in the first place. With such a family, I’m used to translating, and I had already prepared myself for just about any question possible on my book, but I wasn’t expecting this. Excuse me?

– I said that isn’t a processor.

Umm… If you really want to be complicated, I suppose you could argue that it is a microcontroller, since it is based on the Cortex-M0+, but I don’t think that is what she means. What do you mean?

– I changed the processor on my computer a few weeks ago, and a processor is much larger.

The grandmother line has just shifted looks, and is once again analyzing m every move. My opponent is getting more approving nods than I am.

Well, yes, indeed, the processor on your computer is bigger, and if that is what you are looking for, it is better, faster, and just about everything you could imagine. The only problem is… bigger does not mean better. I’ve been in contact with Atmel for some time now, and I’ve been using their products for even longer. I know that they have an impressive range of processor families, and in each family is an even bigger list of members. There is a processor for just about every need. First things first, I need to sort out the Grandmother look.

Okay, so the processor on your computer is larger, indeed. The only thing is, you don’t use it for the same thing, do you?

– You mean that what you have in your hand isn’t powerful?

No, that isn’t what I mean. It is powerful enough. It all depends on what you need. The SAM D20 is an excellent microcontroller, and at 48MHz, it is more than powerful enough for most applications. That gives me an idea…

What kind of car do you drive?

– A medium range, why?

What, you don’t have a sports car? Why not? They are better!

– But I don’t need a sports car!

Exactly. There is a lot of choice, and you decided to go with a model that suits your needs; budget, comfort, utility. If you wanted better, you could have gone with a sports car. You might even have decided to buy a lorry, I mean, the engine is more powerful. It is the same thing with processors. You have a high-end processor in your computer, but do you really want a $500 processor on your wrist, using up so much power that you need a 5-pound battery on your back just to tell the time? The SAM D20 is ultra low powered, you could keep it on your wrist for weeks, maybe even months without a recharge, and it has more than enough power to display the time, and also some bonus features like a thermometer, UV sensor, heart beat monitor, and to record your physical activity and upload that onto your flashy fast computer. It doesn’t heat up as much, and won’t burn your wrist. Plus, it costs a fraction of the price.

I get a majority of approving nods. The granny stare now shifts back to the other person.

– Yes, but processors are getting faster, so why buy something that is slow?

It isn’t slow, not even close. It runs at 48MHz. Let me remind you that your first computer probably ran at 4MHz, and you were happy with that. Processors aren’t only based on their speed in megahertz, and ARM processors are exceptionally fast per megahertz compared to some other design. Also, Atmel added in even more intelligence, making this a very fast and efficient system. Atmel’s Event System makes this ideal for automation, allowing peripherals to react to external events without slowing down processing.

Now, I only have one more person to convince.

– So why would I need one?

Not only do you need one, but you already have several processors like this. Your microwave has one, your car has several to control braking, the radio, the on-board computer and even the different sensors. The world is full of tiny processors, helping us live our lives. And this tiny processor on the SAM D20 Xplained Pro board is one of hundreds of designs from Atmel. My book talks about just some of those designs, and also talks about the SAM D20 Xplained Pro, Atmel’s IDP (Integration Development Platform), and how easy it is to get a project up and running. Five approval nods. I won this one.

– I see what you mean. By the way, when are you going to marry your girlfriend?

Red alert! Five approval nods. I lost this one. Time to go!

Build real-time dashboards to monitor your IoT connected devices

Never to be overlooked is the importance of monitoring connected Internet of Things devices, at both a personal and global scale. You need to know the status of your device; its health, battery, connection status, etc. One way to do that is through a realtime customizable dashboard, enabling you can track, monitor, and visualize your connected devices.

Enter: freeboard.

freeboard is a web-based tool that allows you to build fully customizable and interactive user-interfaces for your connected IoT devices, from dashboards, to consoles, to control panels.

And freeboard now supports PubNub, meaning that you can now monitor your IoT device’s health and status in realtime. Apps and connected devices running on the PubNub Data Stream Network can now integrate data streams with the open source freeboard and customize how the information is displayed.

Monitoring is a powerful tool for any IoT use case. Say you have a number of 3G-connected, GPS-enabled, air-quality sensors attached to city-sponsored rental bikes that can track the air quality down to each city block. When in use, these specially equipped bicycles provide real-time location-tagged air-quality data that is used to create a crowdsourced pollution index map for others bikers to use when planning their routes. All that information can be displayed on a realtime dashboard that looks like this (see it in action here):

Integrating PubNub and freeboard

Both freeboard and PubNub believe in the same core design principles: ease of use, simplicity, and the idea of “it just works.” In the video below, Jim Heising, maker of freeboard, gives a brief demo of using PubNub with freeboard. Additionally, feel free to check out the freeboard GitHub repository.

As we become an increasingly connected world, the importance of monitoring our devices will increase as well. Don’t be left in the dark when it comes to your IoT devices!