Category Archives: Newsworthy

A Bending and Stretching Battery

All electrical and electronic equipment we use in our daily lives requires power to operate. Movable equipment depends on batteries for their mobility. We are used to various types of batteries, like dry cells, lead-acid batteries, rechargeable Ni-Cd and Li-Ion batteries, and so on. However, all the batteries in common use are rigid, non-flexing structures. That may be changing now, as some researchers have claimed to have created a battery that is flexible and stretchable like a snake but unlike a snake, totally safe for humans.

Researchers in Korea claim to have developed a new type of battery that is flexible and stretchable with smooth movements imitating the movements of scales on a snake’s body. However, they have issued assurances that the battery is totally safe for use. This flexible and stretchable battery has a range of applications in contoured devices like wearables and soft robotics.

Although individual scales on the body of a snake are rigid, they can fold together to offer protection against enemies and external forces. The structural characteristics of the scales allow them to move alongside other scales, offering flexibility and stretching capabilities to the snake’s body. At the Korea Institute of Machinery and Materials, researchers from the Ministry of Science and ICT decided to replicate the reptilian characteristics in a mechanical meta structure.

Most conventional wearable devices have the battery in a tight formation with the frame. The new device has several small and rigid batteries in series and parallel connections within a scale-like structure. The researchers ensure the safety of the battery by optimizing its structure so that there is minimum deformation of each battery. They have even optimized the shape of each cell in the battery to offer the highest capacity per unit area.

The connective components and the shape of the battery cell hold the key to this unique device. Each cell is a small hexagonal, resembling the scale on a snake. The researchers have connected each cell with polymer and copper, and there is a hinge mechanism to allow folding and unfolding.

With an aim to mass production in the future, the researchers claim the batteries can be cut and folded with flexible electrodes, with Origami inspiring their manufacturing process.

Wearable devices for humans requiring soft and flexible energy storage can make the best use of these flexible batteries. Another application might be in rehabilitation medical devices for the sick and elderly requiring physical assistance. Soft robots can make use of these flexible batteries as power supply devices at disaster sites when conducting rescue missions. With their ability to freely change shape and move flexibly, these soft robots can move through blocked narrow spaces unhindered by flexible batteries.

Senior researcher, Dr. Bongkyun Jang co-led the research team has commented that mimicking the scales of a snake helped the researchers to develop a flexible battery, making it stretchable and safe to use. The researchers hope that in the future they can develop more soft energy storage devices while boosting their storage capacity. They also hope to develop multi-functional soft robots offering a combination of artificial muscle with actuation technology.

Audio Frequency Range and Electronic Components

A vast majority of people like to listen to some form of audio. Be it in cars, homes, or theaters, audio is prevalent, and its applications are growing with the increasing use of portable devices. In all audio systems, important factors for a portable audio device are its design, size, cost, and quality. But listeners judge the performance of an audio device primarily on the basis of its capability to recreate the necessary audio frequencies.

The audio industry commonly refers to the frequency range that humans can hear and perceive as 20 Hz to 20,000 Hz. Although the average human can distinguish far less than this range, the ability depends on the age and health of the individual. For instance, with age, this range inevitably shrinks, with the loss being more pronounced at the higher frequencies.

Experts divide the perceptible audio spectrum into seven subsets. Starting with the sub-bass subset whose frequency ranges from 16 to 6 Hz, is the primary low range of musical instruments. Then comes the bass frequencies ranging from 60 to 250 Hz, and this is the normal speaking vocal range. Next is the lower mid-range of brass and wood instruments covering the range of 250 to 500 Hz. Mid-range frequencies follow next, covering 500 Hz to 2 kHz, where the higher end of fundamental frequencies of most musical instruments lies. The next range is the higher mid-range, covering 2 to 4 kHz, where the harmonics of most instruments are present. The next range is the presence ranging from 4 to 6 kHz, and this is where the harmonics of string instruments are. The last subset is the brilliance, ranging from 6 to 20 kHz, where the most whiles and whistles are present, and where the harmonics of most percussion instruments lie.

For visualizing and quantifying audio frequencies generate by most audio devices and electronic components, experts rely on frequency response graphs. These graphs are a plot of the sound pressure level at a specified distance plotted against frequency. For instance, a buzzer puts out an audible tone, which features a narrow frequency range on the response graph. On the other hand, audio speakers feature a wide frequency range coverage, as they must recreate sound and voice more faithfully.

A typical frequency response graph for electronic components generating sound depicts the sound pressure level or loudness on its Y-axis on a logarithmic scale, while the X-axis represents frequencies on a logarithmic scale. For electronic devices that sense audio input, such as microphones, the frequency response graph shows sensitivity as sound pressure level on the Y-axis on a logarithmic scale. Most of the frequency response graphs represent a constant power input to the device under measurement.

The frequency response graph is an important document for selecting electronic components for a specific application. For instance, it can differentiate whether a particular speaker will be a good performer for the entire audio frequency range, or it will be suitable for bass frequencies alone. Similarly, the frequency response graph for a microphone will characterize it as suitable for a concert or for instrumentation.

Hybrid Plug-in Connectors for Motor Control Systems

Motor control systems are increasingly becoming more compact while their use is growing with applications in Industry 4.0 and Industrial Internet of Things (IIoT). In fact, motor control systems are prevalent in varied industries like food and beverages, material handling, and robotics. However, as the size of the controller shrinks, designers are facing a new challenge—routing power and signal easily and cost-effectively—while ensuring operator safety and electromagnetic compatibility.

One can use advanced open source interfaces to connect both power and data signals with a single compact connector. Although this does simplify connectivity, the quality, design, and performance of the connector become critical to ensure signal integrity, EMC, and compliance with IP20 requirements.

Designers have moved to Hiperface DSL and SCS open Link, open-source interfaces, to allow the same connector to carry both power and data. This not only saves space but also lowers the cost and simplifies the design of high-performance motor controllers.

The communicating cable has two shielded wires for bi-directional communication based on RS-485, and other wires for encoder power, motor power, and motor brake controls. There are three elements—a three-phase power supply cable, a shielded motor brake cable, a shielded data pair for digital data transfer—enclosed within a shielded cable.

The Hiperface DSL offers a data transmission rate of 9.375 MBaud, over a cable distance of up to 100 meters between the motor controller and the motor. It is possible to transmit data on the cable in two ways—cyclically, given signal and noise conditions, or synchronously with the controller clock.

The motor feedback interface design of the SCS open Link system can supply bidirectional data between the motor and controller. This includes encoder data at rates up to 10 MBaud. It is possible to use two or four-wire implementation. This link is optimized for Industry 4.0, and especially for emerging IIoT solutions, including motor condition monitoring and predictive maintenance.

For SCS open Link and Hiperface DSL to operate reliably, the connection needs optimum shielding between the motor/encoder and its drive. The number of interfaces reduces with the use of plug-in connectors and connection terminals. It is also important to have unbroken shielded cables between the motor/encoder and the drive. However, as the drive connector is non-standard, designers must be careful when designing their own connectors for meeting performance requirements.

OMNIMATE Power Hybrid connectors are an alternative to the SCS open Link and Hiperface DSL. These are a three-in-one solution providing signal, power, and EMC features that implement the SCS open Link and Hiperface DSL protocols. Moreover, the hybrid connectors save space on the motor drive printed circuit board and in the controller cabinet.

The hybrid connectors are available in several configurations. These include six-, seven-, eight-, and nine-position connections. They include power and signal contacts with push-in wire connections. The pitch is 7.62 mm, conforming to the IEC 61800-5-1 and UL 1059 Class C 600 V standards. Several practical design features in the connectors provide high reliability. For instance, the adequate separation between encoder and power connections ensures minimum EMC.

Connectivity Opportunities with 5G

Various parts of the world use different connectivity standards. While some are still struggling with 2, 3, and 4G connectivity, more progressive countries are trying out 5G and 6G. However, since 2019, when the markets introduced 5G, there has been considerable interest in its features. Smartphone manufacturers are now launching new handsets that offer the promise of substantially faster internet access along with the most advanced functionality.

So far, several mobile networks have adopted 5G, the latest and fastest protocol in the market. The recent pandemic forced millions to work from home remotely, and the high-speed wireless communication that 5G offers, came at the most opportune moment.

While manufacturers are busy offering the latest generation of mobile phones to access the 5G wireless telecommunications, many are still not aware of the true impact that the 5G technology has brought us overall. While 5G is a powerful tool for consumers, they are not the sole beneficiaries. 5G is slated to impart a far greater impact to the industrial world as compared to what any other network has so far. In fact, the data speeds offered by 5G are even challenging those from the more traditional wired technologies. This is the first time the world can unshackle itself from a physically wired net.

The introduction of the Internet of Things (IoT) has started the Fourth Industrial Revolution rolling. The IoT brings with it machine-to-machine communications, which, in its basic form, allows electronic devices to share data and communicate without requiring any human intervention. The introduction of 5G began at home, where machines are dominating several tasks in everyday life like grocery shopping to energy metering.

Nevertheless, IoT in future homes is only the tip of the iceberg. The functionality that IoT offers to designers is mind-boggling. The manufacturing world is now reveling in the creation of the smart factory, a byproduct of the Industrial Internet of Things (IIoT).

A traditional factory has several machines, each performing their own tasks, totally isolated from their neighbors. IIoT connects all machines into a network that allows the entire shop floor to act as a single entity. Sharing information among themselves, machines manage not just the production schedules, but also take care of the supply chain, logistics aspects of the operation, and their own maintenance.

With the introduction of 5G communication, the industrial environment will begin to integrate more devices into the smart factory network. A private 5G cell can handle the entire facility while allowing high-speed data flow from all parts of the factory operation, beginning from sensors to the operation of the largest machines. The introduction of a wireless network in the factory brings substantial benefits like unparalleled flexibility. Manufacturers can easily reconfigure production lines to respond to newer demands from the market.

5G communications are not limited to inside the factory premises alone. One of the major users of 5G technology is the automobile industry. While the demand for electric vehicles is growing at a tremendous pace, vehicles are fast becoming autonomous or self-driven. This requires vehicles to communicate with their neighbors on the road. 5G ensures fast communication to promote safety.

Future of LEDs

LEDs have much to offer—small size, high efficiency, and incredible versatility—no wonder they are the most popular electronic products in the market today. Their versatility allows us to use them in horticulture, as status indicator lights, and displays with high definition. Although we are so familiar with LEDs that we hardly notice them anymore, new applications keep appearing, and engineers are forever making newer breakthroughs. That is why the LED market is still growing at a stupendous rate, especially in Europe, India, and Southeast Asia. We have listed some new technologies here:

Multicolor LEDs

After several tries, scientists have recently been able to achieve an LED that produces a blue color. This has completed the entire spectrum of LED arrays. Now, scientists have a technique that allows a single LED to produce all three primary colors. So far, rendering a full spectrum required placing three to four tiny LEDs near one another. The new technique has a big implication of making multicolored displays with color-tuned LEDs.

Furthermore, the new process dopes gallium nitride with europium, a rare earth element, and the process is compatible with current technologies involving GaN. Commercial solid-state lighting commonly uses GaN LEDs, which means we will see the new technology working in the commercial sector very soon.

Cooling with Reversed LEDs

LED physics has another significant new development. Running LEDs in reverse creates a cooling effect. A research team has demonstrated that by running LEDs backward, it is possible to achieve a tiny cooling effect of the order of 6W/m2. This is contrary to the situation in a reverse connected diode, where the diode does nothing.

Researchers are of the opinion they can improve the cooling capacity to 1000W/m2. Although the idea is not yet ready for practical implementation, wearables and mobile devices may benefit from the improved performance from using LEDs to remove heat from processors.

Lighting for Horticulture

Horticulture is benefitting from LED temperature effects and color-tuned lighting. Tomato growers in Belgium have used LEDs to stimulate plant growth. Rather than high-pressure sodium vapor (HPSV) lamps, as is the industry standard, the farmers used LED lighting for their entire 13.3-acre indoor tomato farm.

Although the light from the LEDs appears pink to human eyes, it is actually a mix of red, infra-red, blue, and white LED lights, which the farmers have mixed perfectly for stimulating tomato plant growth. Using Hyperion fittings, the farmers have used new LEDs from Cree. Now, farmers in the UK and the Netherlands are also using these new horticultural LED lamps.

The Belgian farmers were initially skeptical about using LEDs, as these have high efficiency and produce greater amounts of light than heat. They felt LED lights will not provide adequate heat during winter to keep the plants warm. However, they did not need their back-up heating system in the first winter. This proves developments in lighting is effectively reducing payback periods.

The future for LEDs looks bright, with new sources of innovation and recent technological development bringing increasingly superior practical use. Expect more new and improved products in our daily lives with these new LEDs, especially those in color tuning.

Improving Context Awareness in Hearables

On-ear devices, also known as hearables, are one of the fastest-growing devices in the consumer electronics market today. Although at present their role only covers hearing aids and a tool for listening, the on-ear devices have progressed to being wireless. Now there is a brand-new way for engaging this technology to the wider world around us.

Qualcomm conducted a survey in 2019 and found that more than half the respondents were interested in hearables that are context-aware. One of the most useful capabilities the respondents were looking for in hearables was background noise reduction, and the other, dynamic volume adjustment.

The interest that users are showing for these features is for the next-generation of hearables. They are looking for a better, more intensive listening experience. With an increasing interest in hearable, users are now expecting these next-generation features that are currently not available.

For instance, traditional hearables may be wireless but controlled by the phone. While jogging or working out at the gym, it is inconvenient for the user to stare at their phones for adjusting the volume of their headphones. Even with buttons available on the headphones, they are likely to be tiny and not visible when the headphones are on the user’s ears. That makes it very difficult to locate and use the buttons.

One way of improving the user interface would be to add gesture control. Simple gestures and motion tracking can provide instructions for specific actions and controls. For instance, a simple tap on the earbud could mean an increase in volume. Tapping the entire headphone is much simpler than finding and pressing a specific button on it.

A gesture for detecting in-ear presence could automatically pause the audio as soon as the user removes the earbuds from their ears. The audio can resume the moment the user inserts the earbuds back in their ears.

As the range of movement of the human head and ears is relatively consistent compared to that of the pocket or the wrist, hearables can be ideal for tracking fitness. However, motion tracking needs to be precise to not generate false positives and negatives. Therefore, with proper fitness algorithms, it is possible for hearables to track whole body movement such as when running, biking, or standing in a queue. Accurate classification is necessary to convert step counts to calorie counts, providing a more complete picture of the user’s day.

Hearables with spatial audio can change the sound as the head turns, and linked with the accurate head tracking, can put the user right in the center of the orchestra, leading to a truly immersive listening experience. However, this also requires the latency to be low, so that the sound changes with the head movement without delay. This can help and elevate the user’s experience with XR or gaming as well.

Today’s headphones cannot provide the user with the above experience. Users may have to turn down the volume or remove at least one earbud when they want to listen to the external world. This is because the design of the hearables blocks most external sounds to enable the listener to focus on the audio.

Automation Applications of Thermopile Arrays

For a temperature difference occurring between two ends of a thermocouple, it develops an electrical voltage difference. A series of such thermocouples form a thermopile sensor, with each element being a thin wire made from two materials differing in the thermal activity. All the hot junctions of the thermocouples are placed on a thin common absorbing area that forms the sensor face, while the cold junctions are placed on a heat sink with a high thermal mass.

As an instrument, the thermopile sensor can remotely measure the temperature of objects and people. The operation of the thermopile is better understood in terms of heat flow rather than temperature rise. Any object with a temperature higher than the ambient is actually sending out heat in specific spectral characteristics and density. According to primary thermodynamics, heat flows from an object at a higher temperature to another at a lower temperature, causing a change in energy levels of both the objects in the process.

The amount of heat absorbed depends on the field of view and surface area the Thermopile sensor presents to the heat source. Heat reaching the thermocouples inside flows through the membrane structure of the thermopile, finally reaching the heat sink or the housing bottom. This heat flow causes a difference of temperature on the ends of the thermocouples located on the absorber and those on the heat sink, ultimately resulting in a voltage difference between the ends of the thermopile sensor.

Compared to the traditional contact-based temperature sensors, thermopile temperature sensors are of the non-contact type, and hence, they are more popular industrially. Rather than use conduction for heat transfer, thermopile temperature sensors use infrared radiation, allowing better reliability and performance in several constrained applications.

The voltage difference on the ends of the thermopile sensor is analyzed by a Thermopile sensor IC, which provides temperature readout in a convenient digital format. Continuous improvements in this field are resulting in devices that consume reduced power, are smaller and more affordable. This translates into more application opportunities for thermopile temperature sensors in home appliances, office equipment, medical instruments, and consumer devices.

Thermopiles with single-element infrared sensors are popular in the low-end market, as they are good for detecting the presence of stationary warm bodies in a room. However, these simple sensors are unable to provide the direction of movement of a moving object in their field of view. For this additional functionality, engineers use thermopile arrays.

Rather than use a single sensing element as in a thermopile temperature sensor, thermopile arrays use multiple IR sensing elements working together. Integrated signal processing capabilities and coordinated sensing elements of the modern thermopile arrays allow the devices to measure not only absolute temperatures but also temperature gradients. This allows thermopile arrays to sense the direction of movement of the heat source, such as up, down, left, right, and diagonally. Thermopile arrays can detect the presence of multiple objects or people even as they move about in different directions. This allows them to sense the proximity of the heat source and handle control tasks with simple gestures.

Sensors, IoT, and Medical Health

Increasingly, people are looking for preventive care outside of a hospital setting. Medical providers, startups, and Fortune 500 technology companies are all trying out new products and devices for revolutionizing medical care and streamlining costs. While this reduces hospital readmission rates, patients in remote areas are getting the care they need.

The evolving trend is towards remote patient monitoring, which is fundamentally improving the quality of care and patient outcomes right across the medical arena. Moreover, this is happening not only in clinics, onsite in hospitals, and at-home care, but also in remote areas, less populated areas, and in developing countries.

New technologies, new devices, and better results are driving healthcare nowadays. There are several examples of this. For instance, cardiovascular patients can have their heart rates and blood pressure monitored regularly from their homes, with the data feeding back to the cardiologists to allow them to track their patients better. Similarly, doctors are able to track respiration rates, oxygen and carbon dioxide levels, cardiac output, and body temperature of their patients.

Sensors are able to track the weight of patients who are suffering from obstructive heart diseases. This allows doctors to detect fluid retention, and decide if the patient requires hospitalization. Similarly, sensors can monitor the asthma medication of a child to be sure family members are offering it the right dosage. This can easily cut down the number of visits to the ER.

IoT can wirelessly link a range of sensors to measure the vitals in intensive care and emergency units. The first step consists of sensors that generate the data. When tools such as artificial intelligence combine with the sensors, it becomes easy to analyze large amounts of data, helping to improve clinical decisions.

Technological advances such as telemedicine offer advantages in rural hospitals that constantly need more physicians. This often includes remote specialist consultations, remote consultations, outsourced diagnostic analysis, and in-home monitoring. With telemedicine, remote physicians can offer consultations more quickly, making the process cheaper and more efficient compared to that offered by traditional healthcare appointments.

Sensor networks within practices and hospitals are helping to monitor patient adherence, thereby optimizing healthcare delivery. The healthcare industry is increasingly focusing on value-based, patient-centric care, and their outcomes.

This is where the new technology and devices are making a big impact. For instance, data sensors are helping health care providers detect potential issues in the prosthetic knee joint of a patient. The use of sensors allows them to summarize the pressure patterns and bilateral force distribution across the prosthetic. This is of immense help to the patient, warning them to the first indication of strain. The provider can monitor the situation 24/7 and adjust the treatment accordingly, while the payer saves additional expenses on prolonged treatment or recovery.

Integration of IoT features into medical devices has improved the quality and effectiveness of healthcare tremendously. It has made high-value care possible for those requiring constant supervision, those with chronic conditions, and for elderly patients. For instance, wearable medical devices now feature sensors, actuators, and communication methods with IoT features that allow continuous monitoring and transmitting of patient data to cloud based platforms.

Researching Hearing Aids with the Raspberry Pi

All around the world, millions of people benefit from wearing hearing aids. Apart from helping them to hear in a better way, hearing aids lower people’s risk of developing dementia, the likelihood for loneliness, and the possibility of their withdrawing from society.

Testing hearing aids outside the laboratory can be a tough task, but researchers have found the highly popular single board computer, the Raspberry Pi (RBPi) a sound investment for testing hearing aid algorithms. Therefore, for hearing aid research, they are using the RBPi boards.

Although researchers have spent a lot of time and energy for developing hearing aids over the years, there is yet room for improvement. According to a signal processing engineer Tobias Herzke at HorTech in Oldenburg, in Germany, this is especially true for situations that are difficult acoustically. However, the RBPi is proving to be a next-generation research tool for the scientists.

To compensate for an individual’s hearing loss, it is necessary to tailor the amplification and compression in the hearing aid. Researchers plug a monitor to the RBPi and fire up the Fitting GUI for the tailoring.

For this, a spin-off company of the University of Oldenburg has developed openMHA. They have designed openMHA as a common, portable software platform, useful for teaching and researching hearing aid. According to Hendrik Kayser, with the openMHA platform, researchers can process signals in real-time with low delays. Hendrik develops algorithms for processing signals for digital hearing devices.

The software platform openMHA offers a set of standard algorithms that form a complete hearing aid. It can process the signal a live microphone generates to perform different activities such as directional filtering, amplification, feedback suppression, and noise reduction. The RBPi helps in testing new algorithms as this can be difficult with hearing aids alone. The RBPi and openMHA help hearing aid researchers with processing audio signals instantly and adapting to the hearing loss of the individual. The main advantage is the delays between incoming and outgoing audio is below 10 ms. The hearing aid actually has no GUI, except when fitting the amplifier parts.

In the laboratory environment, researchers can execute the openMHA software on Linux computers. According to Tobias, the sound environment will be different within a laboratory from that in an environment that a hearing aid user is likely to encounter in real life. This has often led to wrong results in the past, and did not offer a true reflection of the use of hearing aids. In such situations, the ARM-based single board computer, the RBPi offers a wonderful solution.

By taking advantage of the portable nature of the RBPi, and running openMHA on it, the researchers were able to evaluate newer algorithms in realistic outdoor conditions in real time. In fact, researchers were able to implement a new algorithm running on a mobile device for finding out how the user hears in real time while he is running around wearing a hearing aid.

Using an RBPi means one does not have to carry around a Linux laptop and it is far less expensive. The RBPi offers decent computing capabilities in a small space, while consuming low power.

A Google Assistant with the Raspberry Pi

This is the age of smart home assistants, but not the human kind. The last couple of years a fever pitch has been building up over these smart home assistants, and every manufacture is now offering their own version. While Apple offers Siri, Amazon presents Echo and Alexa, Microsoft wants us to use Cortana, and Google tempts us with Google Home Assistant, there are several more in the race. However, in this melee, Raspberry Pi (RBPi) enthusiasts can make their own smart speaker using the SBC.

Although you can buy Google Home, the problem is it is not available worldwide. However, it is a simple matter to have the Google Assistant in your living room, provided you have an RBPi3 or an RBPiZ. Just as with any other smart home assistant, your RBPi3 home assistant will let you control any device connected to it, simply with your voice.

The first thing you need to communicate with your assistant is a microphone and a speaker. The May issue MagPi, the official RBPi magazine, had carried a nice speaker set sponsored by Google. However, if you have missed the issue, you can use any speaker and USB microphone combination available. The MagPi offer is an AIY Voice Kit for making your own home assistant. AIY is an acronym coined from AI or Artificial Intelligence, and DIY or DO it Yourself.

The MagPi Kit is a very simple arrangement. The magazine offers a detailed instruction set anyone can follow. If you do not have the magazine, the instructions are available on their AIY projects website. The contents of the kit include Voice HAT PCB for controlling the microphone and switch, a long PCB with two microphones, a switch, a speaker, an LED light, a switch mechanism, a cardboard box for assembling the kit, and cables for connecting everything.

Apart from the kit, you will also require additional hardware such as an RBPi3, a micro SD card for installing the operating system, a screwdriver, and some scotch tape.

After collecting all the parts, start the assembly by connecting the Voice HAT PCB. It controls the microphones and the switch, and you attach it to the RBPi3 or RBPiZ using the two small standoffs. Take care to align the GPIO connectors on the HAT to that on the RBPi, and push them in together to connect.

The combination of the HAT board and RBPi will go into the first box. You will need to fold the box taking care to keep the written words on the outside. Place the speaker inside the box first, taking care to align it to the side with the holes. Now, connect the cables to the Voice HAT, and place the combination inside the box.

Next, assemble the switch and LED, inserting the combination into the box. Take care to connect the cables in proper order according to the instructions. As the last step, use the PCB with the two microphones, and use scotch tape to attach it to the box.

Now flash the SD card with the Voice Kit SD image from the website, and insert it into the RBPi. Initially, you may need to monitor the RBPi with an HDMI cable, a keyboard, and mouse.