Stories with Tag Low Power

• An interactive-speed Linux computer made of only 3 8-pin chips

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  Posted: 2025-04-04 19:22:37

  Verbose tl;dr

  Dmitry Grinberg created a remarkably minimal Linux computer using just three 8-pin chips: an ATtiny85 microcontroller, a serial configuration PROM, and a voltage regulator. The ATtiny85 emulates a RISC-V CPU, running a custom Linux kernel compiled for this simulated architecture. While performance is limited due to the ATtiny85's resources, the system is capable of interactive use, including running a shell and simple programs, demonstrating the feasibility of a functional Linux system on extremely constrained hardware. The project highlights clever memory management and peripheral emulation techniques to overcome the limitations of the hardware.

  Dmitry Grinberg, a prolific hardware hacker, has meticulously documented the creation of an extraordinarily minimalist yet functional Linux computer using only three 8-pin integrated circuits. This project, driven by a pursuit of extreme minimalism and a desire to push the boundaries of what's possible with limited resources, showcases a deep understanding of both hardware and software.

  The heart of this diminutive system is the ATtiny85 microcontroller, a remarkably versatile chip despite its limited pin count. Grinberg cleverly leverages the chip's internal peripherals and carefully crafted software to overcome the challenges posed by the scarcity of input/output pins. A significant achievement is the implementation of a USB interface using bit-banging techniques, meaning the ATtiny85 directly manipulates individual data lines to emulate the complex USB protocol without dedicated hardware support. This allows for communication with a host computer.

  Storage is provided by a second ATtiny85, configured as a Serial Peripheral Interface (SPI) flash memory chip. This chip holds the Linux kernel and root filesystem, essential components for any operating system. The use of a second microcontroller for storage, rather than a dedicated flash memory chip, contributes to the project's extreme minimalism.

  The third and final component is a 74HC595 serial-in, parallel-out shift register. This chip expands the limited output capabilities of the main ATtiny85, providing additional control lines necessary for managing the system's various components and interfacing with the external world. It essentially acts as a pin expander, crucial for tasks like driving a display or managing other peripherals.

  Grinberg's approach involves running a specialized, highly optimized version of the Linux kernel, tailored to the extremely constrained environment of the ATtiny85. The user interface is a simple command-line interface accessible through the emulated USB connection. While the resulting system is not powerful enough for complex tasks, it successfully boots Linux and provides a functional command-line environment, demonstrating the impressive feat of running a full-fledged operating system on such limited hardware. The project highlights the power of ingenuity and resourcefulness in pushing the limits of embedded systems.

  • Linux
  • Embedded Systems
  • Microcontroller
  • 8-pin
  • Minimalist Computing
  • Hardware
  • DIY
  • Interactive Speed
  • Low Power
  • Resource Constrained
  • FPGA
  • CPLD

  Summary of Comments ( 104 )
  https://news.ycombinator.com/item?id=43586654

  Verbose tl;dr

  Hacker News users discussed the practicality and limitations of the 8-pin Linux computer. Several commenters questioned the usefulness of such a minimal system, pointing out its lack of persistent storage and limited I/O capabilities. Others were impressed by the technical achievement, praising the author's ingenuity in fitting Linux onto such constrained hardware. The discussion also touched on the definition of "running Linux," with some arguing that a system without persistent storage doesn't truly run an operating system. Some commenters expressed interest in potential applications like embedded systems or educational tools. The lack of networking capabilities was also noted as a significant limitation. Overall, the reaction was a mix of admiration for the technical feat and skepticism about its practical value.

  The Hacker News post titled "An interactive-speed Linux computer made of only 3 8-pin chips" generated several comments discussing the project and its implications.

  Several commenters expressed fascination and admiration for the project's minimalism and ingenuity. They praised the creator's ability to achieve a functional Linux system with such limited resources. Some described the project as "amazing" and "impressive," highlighting the technical skill involved in making such a constrained system work.

  A significant portion of the discussion revolved around the practicality and potential applications of such a minimalist system. Some questioned the real-world usefulness of a computer with such limited capabilities, while others envisioned potential applications in embedded systems, education, and as a platform for learning about low-level computing. One commenter suggested it could be useful for teaching computer architecture.

  The choice of chips and their specific roles in the system were also discussed. Commenters inquired about the functionality of each chip, with particular interest in how the system managed memory and peripherals. The creator's choice of an ATtiny85 microcontroller, coupled with an FTDI chip for USB connectivity and an SPI flash chip for storage, sparked conversations about the trade-offs between simplicity, cost, and performance.

  Several commenters delved into the technical details of the project, discussing topics such as bootloaders, memory management, and the limitations imposed by the chosen hardware. They explored the challenges involved in running Linux on such a resource-constrained system and speculated about potential optimizations and improvements. One commenter highlighted the significance of using a microcontroller designed for lower power applications compared to a previous iteration using a different microcontroller.

  There was also some discussion about the definition of "interactive speed." Some commenters pointed out that the system's performance was likely limited, with potentially slow response times. They debated whether the term "interactive" accurately reflected the user experience.

  Finally, some commenters drew parallels to other minimalist computing projects and discussed the broader trend of pushing the boundaries of what's possible with limited hardware. They shared links to similar projects and resources, fostering a sense of community and shared interest in minimalist computing.

• Tiny Ten DSP-Based HF Transceiver

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  Posted: 2025-03-02 14:34:50

  Verbose tl;dr

  The TinyTen is a compact, highly portable, and experimental high-frequency (HF) transceiver built around a low-power DSP. It utilizes direct digital synthesis (DDS) for both transmit and receive, covering 160 through 10 meters, with a maximum output power of 1W. The design prioritizes simplicity and small size, featuring a minimalist user interface with a single rotary encoder and a small LCD display. It requires an external computer for initial configuration and incorporates readily available components for easier construction by amateur radio enthusiasts. Despite its experimental nature, the TinyTen aims to deliver a functional and portable HF experience.

  The "Tiny Ten" project details the design and construction of an exceptionally compact, digitally-driven high-frequency (HF) transceiver for amateur radio operation. This ambitious endeavor leverages the power of a Digital Signal Processor (DSP), specifically the Analog Devices ADSP-BF533, to perform the majority of signal processing tasks, enabling a remarkably small physical footprint. The radio covers the 7 MHz amateur band, commonly referred to as the 40-meter band, and utilizes a direct-conversion architecture, also known as zero-IF, simplifying the analog circuitry required.

  The receiver employs a single-chip solution for mixing and analog-to-digital conversion, further contributing to the miniaturization. The incoming RF signal is digitized directly and processed within the DSP. The core functionalities of the receiver, including filtering, demodulation, and automatic gain control (AGC), are all implemented in software on the DSP. This digital approach offers a high degree of flexibility and allows for advanced features to be incorporated with relative ease.

  For transmission, the DSP generates the desired output signal digitally. This digitally-generated signal is then converted back to analog using a digital-to-analog converter (DAC) and subsequently upconverted to the target frequency. A power amplifier stage boosts the signal to the desired output power level for transmission. Similar to the receiver, the transmitter benefits from the flexibility and precision offered by the DSP-based architecture.

  The user interface consists of a small LCD display and a few control buttons, facilitating frequency selection, mode selection, and other operational parameters. The compact nature of the design necessitates a streamlined interface, but the essential controls are provided for practical operation. The radio is powered by a standard 12-volt DC supply, making it suitable for portable or mobile use.

  The author meticulously documents the design process, including schematic diagrams, board layouts, and firmware details. The project highlights the capabilities of modern DSPs in enabling sophisticated radio functionality within a remarkably small and power-efficient package. The Tiny Ten showcases a compelling example of a miniature HF transceiver that leverages digital signal processing to achieve impressive performance in a constrained form factor. While operating only on the 7 MHz band, it demonstrates the potential of this approach for other frequency bands and more advanced features.

  • DSP
  • HF
  • Transceiver
  • Radio
  • Amateur radio
  • Ham radio
  • Digital Signal Processing
  • Embedded Systems
  • Electronics
  • Shortwave
  • TinyTen
  • QRP
  • Low Power
  • portable radio
  • SDR
  • Software Defined Radio

  Summary of Comments ( 9 )
  https://news.ycombinator.com/item?id=43230864

  Verbose tl;dr

  Hacker News users discuss the TinyTen transceiver with interest, focusing on its impressive DSP capabilities and small size. Several commenters express admiration for the project's ingenuity and the author's clear explanations. Some discuss the trade-offs of DSP-based radios, noting potential performance limitations compared to traditional analog designs, particularly regarding dynamic range and strong signal handling. Others are curious about the specifics of its DSP implementation and the choice of components. A few share personal experiences with similar projects and offer suggestions for improvements or alternative approaches. The overall sentiment is positive, with many praising the project as a fascinating example of modern radio design.

  The Hacker News post titled "Tiny Ten DSP-Based HF Transceiver" discussing the Tiny Ten transceiver project sparked a relatively short but engaged discussion. Several commenters expressed admiration for the project's ambition and technical achievements.

  One commenter highlighted the impressive nature of achieving a full HF transceiver in such a small form factor, particularly noting the challenges of integrating features like a spectrum display and waterfall within the limited screen space. They also lauded the choice of the STM32H7 microcontroller, recognizing its capabilities while acknowledging the potential difficulties in harnessing its full potential. The same commenter later added a point about the potential legal complexities of selling a device with a built-in spectrum analyzer function, depending on the specific regulations of different regions.

  Another commenter focused on the user interface, expressing concern about the potential difficulty of operating the device with such limited controls and display. They acknowledged the impressive feat of fitting all the functionality in, but questioned the practical usability for extended periods. This commenter also pointed to the Xiegu G90 as an example of a similarly small transceiver, inviting comparison and implicitly suggesting potential UI/UX improvements.

  The developer of the Tiny Ten transceiver also participated in the discussion, responding to the concerns about user interface complexity. They acknowledged the challenges and indicated that a larger version with a more extensive user interface was already under development. They also clarified the status of the project, stating that it was still a prototype and not yet ready for commercial release.

  The rest of the comments are brief expressions of interest, appreciation for the project, or requests for more information. Notably, there's a recurring interest in the user interface and the practicality of using such a compact device, reflecting the common thread of balancing functionality and usability in miniaturized electronics.

• Just barely fitting a full wi-fi stack on the nRF9151

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  Posted: 2025-02-18 08:24:30

  Verbose tl;dr

  This blog post details the author's successful, yet extremely tight, implementation of a full Wi-Fi networking stack (including TLS) on the memory-constrained nRF9160. Using the Zephyr RTOS, they managed to squeeze in lwIP, mbedTLS, and other necessary components, leaving only about 1KB of RAM free. This required careful configuration and optimization, particularly within lwIP, to minimize memory usage without sacrificing essential functionality. The author highlights the challenges of working with the nRF9160's limited resources and shares specific configuration adjustments, such as reducing TCP window size and disabling IPv6, that enabled them to achieve a working Wi-Fi connection. The post serves as a practical demonstration of pushing the boundaries of what's possible on this resource-constrained platform.

  Daniel Mangum's blog post, "Just barely fitting a full wi-fi stack on the nRF9160," details his challenging but successful endeavor to implement a complete Wi-Fi station functionality on the memory-constrained nRF9160 System-in-Package (SiP), a device primarily designed for cellular IoT applications. The nRF9160, known for its low power consumption and integrated LTE-M/NB-IoT modem, possesses a relatively limited amount of RAM (256KB) and flash memory (1MB), making the integration of a resource-intensive Wi-Fi stack a significant undertaking.

  The author initially attempted to utilize the readily-available lwIP (lightweight IP) stack, a popular choice for embedded systems due to its small footprint. However, even after aggressive configuration optimization, lwIP, coupled with the necessary Wi-Fi driver and related dependencies, exceeded the nRF9160's available RAM. This led to exploring alternative, even smaller TCP/IP stacks.

  After considerable research and experimentation, Mangum identified the uIP (micro IP) stack as a viable candidate. uIP, designed specifically for extremely resource-constrained environments, offered a significantly reduced memory footprint compared to lwIP. However, integrating uIP with the nRF9160's Wi-Fi subsystem presented its own set of challenges. The process involved intricate memory management strategies, careful selection and configuration of supporting libraries, and meticulous optimization of the entire software stack.

  The author meticulously describes the modifications and configurations required to successfully integrate uIP with the nRF9160, highlighting the various trade-offs made to achieve a functional Wi-Fi station within the limited memory constraints. This included disabling certain features and optimizing buffer sizes to minimize RAM usage.

  Ultimately, Mangum managed to fit a complete Wi-Fi station implementation, including the uIP stack, the required drivers, and all necessary supporting libraries, within the nRF9160's restricted memory. The post emphasizes the tightness of the fit, implying that further additions or expansions to the software stack would likely be impossible without exceeding the available resources. The successful implementation, despite the inherent challenges, demonstrates the feasibility of utilizing the nRF9160 for applications requiring both cellular and Wi-Fi connectivity, albeit with careful consideration and optimization of the software stack. The author's work opens up possibilities for using the nRF9160 in scenarios demanding dual connectivity within a single, power-efficient device.

  • nRF9160
  • nRF9151
  • Nordic Semiconductor
  • IoT
  • Wi-Fi
  • Embedded Systems
  • Firmware
  • Low Power
  • Cellular IoT
  • Wireless Communication
  • networking
  • Zephyr RTOS

  Summary of Comments ( 0 )
  https://news.ycombinator.com/item?id=43087288

  Verbose tl;dr

  Hacker News users discussed the challenges and ingenuity of fitting a full Wi-Fi stack onto the resource-constrained nRF9161. Several commenters expressed admiration for the author's accomplishment, highlighting the difficulty of working with such limited resources. Some questioned the practical applications, given the nRF9161's integrated cellular modem and the availability of smaller, cheaper Wi-Fi microcontrollers. Others suggested potential uses like captive portals or bridging between cellular and local networks. The Zephyr RTOS was mentioned as a contributing factor to the project's success due to its small footprint. One commenter shared their experience with similar memory constraints on embedded systems and offered debugging advice. The discussion also briefly touched on the implications of this achievement for IoT devices and the potential for further development in low-resource Wi-Fi applications.

  The Hacker News post "Just barely fitting a full wi-fi stack on the nRF9151" has generated several comments discussing the challenges and implications of running a Wi-Fi stack on a resource-constrained device like the nRF9160.

  One commenter highlights the difficulty of fitting lwIP (a lightweight TCP/IP stack) onto the nRF91, pointing out that even with optimizations, it barely fits within the limited RAM. They express surprise that the author managed to squeeze it in, acknowledging the impressive feat. This comment also mentions that the real challenge lies not just in fitting the stack, but also in ensuring stable and reliable operation given the tight memory constraints.

  Another comment chain delves into the intricacies of memory management within embedded systems like the nRF91, specifically discussing the separation of the application processor from the network processor. This separation introduces complexities in memory allocation and communication, influencing the overall performance and stability of the Wi-Fi implementation.

  Further discussion revolves around the trade-offs between using the nRF91's built-in LTE modem versus adding Wi-Fi functionality. While the nRF91 is designed primarily for cellular IoT applications, some commenters express the need for Wi-Fi in specific scenarios, either as a backup connectivity option or for local network access. The comments weigh the pros and cons of each approach, considering factors like power consumption, cost, and complexity.

  A user questions the choice of not using the ESP32, a popular microcontroller known for its integrated Wi-Fi capabilities. The author responds, clarifying that the nRF91 was chosen for its integrated cellular modem and the project's specific requirement for both cellular and Wi-Fi connectivity in a single device. This exchange emphasizes the importance of selecting the right hardware for the intended application, considering factors beyond just Wi-Fi capability.

  Several other comments express general interest in the project and appreciate the author's detailed write-up of their experience. They acknowledge the complexity of working with resource-constrained devices and applaud the author's ingenuity in making it work.

• A 10-Year Battery for AirTag

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  Posted: 2024-12-18 18:17:17

  Verbose tl;dr

  ElevationLab introduces TimeCapsule, a protective case for Apple AirTags designed to last for the AirTag's entire lifespan. It incorporates a replaceable CR2032 battery, addressing the AirTag's limited battery life. Made of stainless steel with a cavity to improve signal strength, TimeCapsule includes a keyring and is designed to be more durable and easier to find in bags than the bare AirTag. It effectively transforms the AirTag into a key-sized tracker with a user-replaceable battery estimated to last about ten years.

  ElevationLab, a company known for its accessories for Apple products, has announced the "TimeCapsule," a meticulously engineered replacement battery compartment designed to significantly extend the lifespan of an Apple AirTag. Recognizing that AirTags are inherently disposable due to their sealed, non-replaceable battery, ElevationLab sought to create a solution for environmentally conscious consumers and those seeking long-term tracking solutions. The TimeCapsule boasts a remarkable projected lifespan of ten years, eliminating the need for frequent replacements and reducing electronic waste. This longevity is achieved through the utilization of a specialized low-power lithium thionyl chloride (LTC) battery chemistry known for its exceptional shelf life and stability. This chemistry, while offering extended operational duration, does necessitate a slightly larger form factor compared to the standard AirTag battery. However, ElevationLab has skillfully minimized the size increase, resulting in a form factor only 2.1mm thicker and 2mm wider than the original AirTag, a negligible difference considering the substantial lifespan extension.

  The TimeCapsule's design not only focuses on longevity but also on ease of use and maintainability. The battery compartment is readily accessible, allowing users to replace the LTC battery themselves with a standard CR2432 battery, readily available from various retailers. This user-replaceable design further contributes to the product's sustainability. Furthermore, the TimeCapsule is constructed from high-quality materials, ensuring durability and longevity to match the impressive battery lifespan. The design incorporates a robust stainless steel shell that protects the internal components and complements the aesthetic of the AirTag, maintaining its sleek and minimalist appearance. The installation process is designed to be straightforward, allowing users to easily integrate the TimeCapsule with their existing AirTags without specialized tools or technical expertise. This considered approach reflects ElevationLab's commitment to providing practical and user-friendly solutions. The TimeCapsule represents a significant advancement in AirTag functionality, transforming it from a disposable tracking device into a sustainable, long-term solution.

  • AirTag
  • Battery
  • Long-lasting Battery
  • 10-Year Battery
  • TimeCapsule
  • ElevationLab
  • Battery Replacement
  • Find My
  • Apple
  • Accessories
  • IoT
  • Low Power
  • Ultra-low Power
  • Power Efficiency
  • CR2032
  • User-replaceable Battery
  • Crowdfunding
  • Product Announcement

  Summary of Comments ( 563 )
  https://news.ycombinator.com/item?id=42453207

  Verbose tl;dr

  HN commenters are generally skeptical of the TimeCapsule's claimed 10-year battery life, with several pointing out the impracticality of such a long timeframe for a tracking device. Many suspect the battery will degrade significantly before the 10-year mark, rendering the device useless much sooner. Some users question the actual utility of the product, wondering about real-world scenarios where a decade-long tracking solution would be necessary or even desirable. Others express privacy concerns about the potential for long-term, unnoticed tracking. A few commenters mention the environmental impact of disposable electronics, especially given the long lifespan and specialized battery. Several suggest alternative solutions, including replaceable batteries or solar charging. Overall, the sentiment is one of cautious disbelief and concern over practical limitations and unintended consequences.

  The Hacker News post titled "A 10-Year Battery for AirTag" sparked a discussion with several interesting comments. Many commenters focused on the implications of a longer-lasting battery, particularly in the context of tracking stolen items.

  One compelling comment pointed out that the real issue with AirTags isn't battery life, but the fact that thieves can often quickly locate and disable them. A longer battery life wouldn't necessarily address this fundamental vulnerability. This commenter suggested that a more effective solution might be integrating AirTags more deeply into devices, making them harder to remove.

  Another commenter questioned the trade-offs associated with a 10-year battery. They speculated about the size and cost implications of such a battery, wondering if it would make AirTags significantly larger or more expensive. This raised a broader discussion about the optimal balance between battery life, size, and cost for tracking devices.

  Several comments highlighted the environmental impact of disposable batteries. While a 10-year lifespan would reduce battery waste, some commenters argued for rechargeable batteries as a more sustainable approach. They also discussed the potential for solar-powered AirTags as a longer-term solution.

  There was also a discussion about the feasibility of the claimed 10-year battery life. Some commenters expressed skepticism, suggesting that real-world usage patterns and environmental factors could significantly impact battery performance. They called for more transparency regarding the testing methodology used to arrive at the 10-year figure.

  Finally, some comments touched upon the privacy implications of long-term tracking devices. The possibility of someone secretly placing an AirTag with a 10-year battery on a person or vehicle raised concerns about potential misuse and the need for robust anti-stalking measures.