WhatCable: Unveiling the Secrets of Your USB-C Cables
In the world of technology, where cables and connectors are ubiquitous, it's easy to overlook the importance of their performance and reliability. But what if there was a way to uncover the hidden truths about your USB-C cables? Enter WhatCable, a free Mac app that acts as a detective, revealing the secrets of your USB-C cables and devices. This innovative tool, created by Darryl Morley, harnesses the power of Apple's own data collection to provide valuable insights into the performance and capabilities of your USB-C connections.
Unlocking the Power of Apple's Data
WhatCable's magic lies in its ability to read and interpret the data that Apple's Mac operating system already collects about connected USB devices. By leveraging Apple's public APIs, WhatCable accesses information that is typically not available to users. It focuses on the USB Power Delivery negotiation process, where the port controller chip on Apple Silicon Macs plays a crucial role. When a USB-C cable with an e-marker is connected, the port controller sends a 'Discover Identity' message, and the e-marker responds with details such as vendor ID, speed rating, current rating, voltage limits, and more.
This response is then written into the IOKit registry by macOS. WhatCable cleverly reads this data, providing a comprehensive view of the connected cable and device. It goes beyond the e-marker's claims, considering the actual negotiated connection speed, Thunderbolt link speed, and live voltage and current at each port. By combining this information, WhatCable offers a detailed analysis of the current connection, identifying bottlenecks and ensuring optimal performance.
Real-World Testing and Insights
The author puts WhatCable to the test with a variety of USB-C cables, showcasing its capabilities and limitations. For instance, a Satechi cable, despite reporting USB 2.0 speeds, is capable of delivering 100W charging, which is close to the Mac's charging limit. WhatCable accurately identifies this, providing valuable information that goes beyond the e-marker's claims. On the other hand, a cable advertised as 10Gbps USB 3, but WhatCable reveals it only supports USB 2.0 speeds, saving the user from potential disappointment.
The app also highlights the importance of cable quality. A daily driver cable, showing signs of wear, fails to deliver the expected 10Gbps speed when connected to a fast SSD. WhatCable's ability to detect and analyze such issues is a game-changer for users who want to ensure their cables are up to the task.
A Free Yet Powerful Tool
WhatCable stands out for its free nature, offering a wealth of information without any cost. Creator Darryl Morley emphasizes that the app will remain free at its core, with an optional Pro version available for £9.99. This Pro version enhances the experience with real-time power monitoring, diagnostics, and a terminal view, providing even deeper insights into the USB-C ecosystem.
Beyond macOS: Future Plans and Limitations
Morley's vision extends beyond macOS, as he acknowledges the challenges of building a Windows version due to hardware variance and API limitations. Android and iOS also present similar obstacles. However, he is actively working on a Linux port, ensuring that users on different operating systems can benefit from this innovative tool.
In conclusion, WhatCable is a fascinating and powerful tool that empowers users to make informed decisions about their USB-C cables. By harnessing Apple's data and providing detailed insights, it becomes an essential companion for tech enthusiasts and professionals alike. As Morley continues to refine and expand its capabilities, WhatCable is set to become an indispensable asset in the world of USB-C connectivity.
