Stories with Tag Atom

• A technical history of Acorn Computers

  permalink

  Posted: 2025-03-10 14:35:05

  Verbose tl;dr

  Acorn Computers, born from a Cambridge-based electronics shop, evolved from early microcomputers like the System 1 to the iconic BBC Micro, fueled by a partnership with the British Broadcasting Corporation. This success spurred further development, including the ARM architecture, born from the Acorn RISC Machine project, and the Archimedes range utilizing this new processor. Despite innovative designs like the Acorn RISC PC and the Network Computer, Acorn struggled against the growing dominance of the PC market. Ultimately, Acorn transitioned into ARM Ltd, focusing solely on the increasingly successful ARM processor design, leaving behind its legacy of influential computers and its profound impact on the UK computing landscape.

  This extensive online resource meticulously chronicles the technical evolution of Acorn Computers Ltd., a British company that played a pivotal role in the personal computer revolution, particularly in the UK. The narrative begins with Acorn's humble beginnings in 1978, originating from a Cambridge-based electronics consultancy named CPU (Cambridge Processor Unit). The site details the initial projects undertaken by CPU, laying the groundwork for Acorn's subsequent emergence.

  The narrative progresses through Acorn's early microcomputer systems, starting with the Acorn System 1, a kit-based machine designed for hobbyists. The subsequent System 2, System 3, and System 4 are discussed, emphasizing their incremental advancements in hardware capabilities and design. The piece then delves into the Atom, highlighting its significance as a more polished and commercially viable product, powered by the 6502 processor. This discussion includes details of the Atom's architecture, expansion capabilities, and its role in establishing Acorn's foothold in the burgeoning personal computer market.

  A significant portion of the history focuses on the BBC Microcomputer, arguably Acorn's most iconic creation. The story unfolds with the BBC's Computer Literacy Project and Acorn's winning bid to produce the educational machine that would become synonymous with a generation of British computer users. The site painstakingly details the technical specifications of the BBC Micro, including its MOS Technology 6502 processor, sophisticated video capabilities, and its innovative use of a second processor, the Ferranti ULA (Uncommitted Logic Array). The various models of the BBC Micro, including the Model A, Model B, and the later Model B+, are examined, highlighting their distinct features and enhancements.

  The narrative then transitions to the Acorn Electron, a cost-reduced version of the BBC Micro aimed at the home market. The Electron's design compromises and its eventual fate are explored. The subsequent rise of the Acorn Archimedes range is discussed, emphasizing its revolutionary use of the ARM (Acorn RISC Machine) processor, a groundbreaking architecture that would go on to dominate the mobile computing landscape. The architecture of the Archimedes, its operating system (RISC OS), and its performance advantages are examined in detail.

  The later years of Acorn are also covered, including the development of the A3000, A4000, A5000, and Risc PC series of computers. The site details the evolving ARM processors used in these machines, the advancements in RISC OS, and the changing market dynamics that influenced Acorn's strategic decisions. The eventual shift in Acorn's focus towards the ARM processor business, culminating in the formation of ARM Holdings, is also chronicled.

  The site’s comprehensive approach includes numerous photographs, diagrams, and technical specifications of the various Acorn systems, providing a rich and detailed picture of their evolution. The narrative effectively captures the innovative spirit of Acorn Computers, its contribution to the personal computer industry, and the enduring legacy of the ARM processor. The document serves as a valuable resource for anyone interested in the history of computing, particularly the pivotal role played by Acorn Computers in shaping the technology we use today.

  • Acorn Computers
  • BBC Micro
  • Arm
  • RISC OS
  • British Computing
  • Retrocomputing
  • computer history
  • technology history
  • Acorn Archimedes
  • Electron
  • Atom
  • A3000
  • A5000

  Summary of Comments ( 1 )
  https://news.ycombinator.com/item?id=43321131

  Verbose tl;dr

  Hacker News users discuss the linked history of Acorn Computers, praising its comprehensiveness and detailed technical information. Several commenters reminisce about their experiences with Acorn machines, particularly the BBC Micro and Archimedes, highlighting their role in the UK's computing history and education. Some discuss the innovative features of Acorn's RISC architecture and its influence on ARM processors. Others mention Acorn's business struggles and the eventual dominance of x86, while acknowledging the company's lasting legacy through ARM. A few users also share personal anecdotes about using Acorn machines for programming, gaming, and even running small businesses. The overall sentiment is one of nostalgia and appreciation for Acorn's contributions to the computing world.

  The Hacker News post titled "A technical history of Acorn Computers" sparked a lively discussion with several insightful comments. Many users reminisced about their experiences with Acorn machines, highlighting their influence and innovation.

  One commenter shared a personal anecdote about their school acquiring a BBC Micro and how it ignited their passion for programming. They fondly recalled the excitement of using the machine and the impact it had on their career trajectory. This sentiment was echoed by others who expressed similar formative experiences with Acorn computers, emphasizing the accessibility and educational value of the platform.

  Another commenter delved into the technical aspects of the Acorn Archimedes, praising its advanced RISC architecture and the innovative ARM processor. They highlighted the forward-thinking design of the Archimedes and how it paved the way for the ubiquitous ARM processors found in countless devices today. This point sparked further discussion about the technical merits of Acorn's designs and their lasting legacy in the computing world.

  The conversation also touched upon the business aspects of Acorn, with some commenters lamenting the company's eventual decline and acquisition. They discussed the challenges Acorn faced in competing with larger players in the market and speculated on alternative paths the company could have taken.

  Several users mentioned the role of the BBC Micro in the UK education system and its impact on a generation of programmers and computer enthusiasts. They discussed the educational software available for the platform and how it fostered a culture of learning and experimentation.

  Some commenters also pointed out the influence of Acorn on the development of the RISC-V architecture, drawing parallels between the design philosophies of both. They discussed the open-source nature of RISC-V and its potential to carry on the legacy of Acorn's innovative approach to computer architecture.

  Overall, the comments section paints a picture of Acorn as a highly influential company with a dedicated following. The users' recollections and technical insights provide a valuable perspective on Acorn's contributions to the computing world and its lasting impact on the industry.

• Parinfer: Simpler Lisp Editing

  permalink

  Posted: 2025-01-20 08:21:16

  Verbose tl;dr

  Parinfer simplifies Lisp code editing by automatically managing parentheses, brackets, and indentation. It offers two modes: "Paren Mode," where indentation dictates structure and Parinfer adjusts parentheses accordingly, and "Indent Mode," where parentheses define the structure and Parinfer corrects indentation. This frees the user from manually tracking matching delimiters, allowing them to focus on the code's logic. Parinfer analyzes the code as you type, instantly propagating changes and offering immediate feedback about structural errors, leading to a more fluid and less error-prone coding experience. It's adaptable to different indentation styles and supports various Lisp dialects.

  Parinfer, introduced by Shaun Lebron, proposes a novel approach to editing Lisp code, aiming to simplify the traditionally cumbersome process of managing parentheses. It operates on the principle of maintaining structural consistency, automatically adjusting parentheses as the user types code, eliminating the need for manual insertion, deletion, or matching.

  The system works by allowing developers to focus on either the content of their code (referred to as "Paren Mode") or the structure represented by parentheses (referred to as "Indent Mode"). In Paren Mode, users type code as they normally would, adding and removing characters. Parinfer intercepts these changes and intelligently adjusts the surrounding parentheses to maintain proper syntactic balance. This eliminates the common errors associated with mismatched or missing parentheses, allowing for a more fluid and uninterrupted coding experience.

  Conversely, in Indent Mode, the user manipulates the indentation of the code, which Parinfer interprets as instructions for modifying the parenthetical structure. Changes in indentation will automatically insert, delete, or reposition parentheses to reflect the intended nesting of expressions. This offers an alternative approach to structuring code, leveraging the visual cues of indentation for greater clarity and ease of manipulation, especially in deeply nested expressions.

  Parinfer supports a wide range of Lisp dialects, including Clojure, Scheme, Common Lisp, and Racket, demonstrating its adaptability and broad applicability within the Lisp ecosystem. It is not tied to any specific editor, being implemented as a library that can be integrated into various editing environments. This portability makes it accessible to a wider audience of Lisp programmers, regardless of their preferred tools.

  The system strives to be minimally invasive, ensuring that edits are predictable and understandable. It operates on a clear set of rules that govern the interaction between typed characters, indentation, and the resulting parenthetical structure. This predictability is crucial for building trust in the system and allowing users to confidently rely on Parinfer to handle the intricacies of parenthesis management. Furthermore, the simplicity of its design aims to reduce the cognitive load associated with editing Lisp code, freeing the developer to focus on the logic and algorithms of their programs rather than the syntactical overhead.

  • Lisp
  • editing
  • Parinfer
  • Code Editor
  • programming
  • syntax
  • Parentheses
  • Indentation
  • Clojure
  • Scheme
  • Racket
  • Emacs
  • vim
  • Atom
  • Sublime Text
  • IDE
  • developer tools
  • Software Development

  Summary of Comments ( 9 )
  https://news.ycombinator.com/item?id=42766205

  Verbose tl;dr

  HN users generally praised Parinfer for making Lisp editing easier, especially for beginners. Several commenters shared positive experiences using it with Clojure, noting improvements in code readability and reduced parenthesis-related errors. Some highlighted its ability to infer parentheses placement based on indentation, simplifying structural editing. A few users discussed its potential applicability to other languages, and at least one pointed out its integration with popular editors. However, some expressed skepticism about its long-term benefits or preference for traditional Lisp editing approaches. A minor point of discussion revolved around the tool's name and how it relates to its functionality.

  The Hacker News post "Parinfer: Simpler Lisp Editing" generated a moderate discussion with several commenters sharing their experiences and perspectives on Parinfer and Lisp editing in general.

  Several users praised Parinfer for its innovative approach to structural editing, finding it significantly easier and less error-prone than traditional parenthesis management in Lisp. One commenter stated that it transformed their Clojure editing experience, eliminating the constant struggle with parentheses and allowing them to focus on the code's logic. Another shared that Parinfer made them enjoy writing Lisp again after previous frustrations. The intuitive nature of Parinfer's paren-handling and its ability to infer correct structure was highlighted as a key advantage.

  Some users compared Parinfer favorably to other structural editing tools and techniques, such as Paredit. While acknowledging Paredit's power, they found Parinfer's approach simpler to learn and use, leading to a more fluid coding experience. One comment specifically mentioned the reduced cognitive load when using Parinfer compared to Paredit. However, other users expressed a preference for Paredit, arguing that its explicit commands offered more control and predictability. This sparked a brief discussion on the merits of different approaches to structural editing.

  A few commenters raised potential drawbacks of Parinfer. One concern was the learning curve associated with a new editing paradigm, although some argued that this was minimal compared to the benefits. Another commenter mentioned the possibility of unexpected behavior in certain edge cases, suggesting that understanding the underlying rules of Parinfer is important for effective use. A desire for better editor integration and more comprehensive documentation was also expressed.

  The discussion also touched upon broader topics related to Lisp and code editing. One comment highlighted the historical challenges of Lisp editing and how tools like Parinfer address these issues. Another discussed the importance of proper tooling for enhancing developer productivity and enjoyment. A commenter also mentioned the relevance of Parinfer's approach to other languages with significant syntactic structure, suggesting potential applications beyond Lisp.

  Overall, the comments reflect a generally positive reception of Parinfer, with many users appreciating its simplified approach to Lisp editing. While some concerns and alternative viewpoints were presented, the overall sentiment suggests that Parinfer offers a compelling solution to a longstanding challenge in Lisp programming.