Analog i

Deimos

Realtime data acquisition and controls ecosystem, including hardware, firmware, and software.

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Hardware Peripherals

Controller Comm. Media

Communication with peripherals is done via message passing on an arbitrary socket. New communication media can be used by implementing the Socket trait.

While the controller can accommodate multiple communication media, a peripheral will typically only implement one method for reliability reasons.

Several more socket implementations are planned, including TCP, UDP/IPV6, and thread channel message passing.

Data Integrations

Data integration implementations perform I/O and database transactions on a separate core to avoid blocking the main control loop, unless no separate core is available.

Calculation Functions

... in addition to a variety of unremarkable math functions.

Goals and Anti-Goals

The goals of this ecosystem are:

• Tightly-integrated sensor frontends
• Fully independent input and output channels; every advertised channel is available at the same time
• Full reassertion of state at each control cycle; robust to packet loss
• SI-traceable calibrations
• Control program without required root/admin access or drivers
• Run on standard networking hardware with sub-microsecond time sync
• Semantic versioning for both hardware and software to prevent unexpected breaking changes
• 100% end-to-end open-source hardware, firmware, and software under permissive licenses

Notable anti-goals:

• Copyright mongering
• "Internet-of-Things" (IoT) functionality
• Over-the-Air (OTA) firmware updates
• Performative complexity
• Skimping on bits

Versioning

To prevent unexpected breaking changes, both software and hardware use semantic versioning and, whenever possible, use procedural semver linting to avoid unexpected or unintuitive breakage.

Semantic versioning of hardware is not yet a well-established practice. Here, it is taken to cover both hardware and accompanying firmware, and their interfaces:

• Major version: Potentially breaking changes
  • Examples: Removing a channel, increasing filter phase lag, narrowing samplerate range, or changing packet interchange format, reducing overvoltage tolerance
    • Adding a channel is also a breaking change if it affects packet interchange format
  • Notable non-examples: Changing connector types for sensors without a noise-level or thermoelectric voltage sensitivity, changing model number
• Minor version: Backward-compatible changes
  • Examples: Adding a channel, increasing samplerate range, decreasing filter phase lag, increasing overvoltage tolerance
• Patch version: Forward- and backward- compatible changes
  • Examples: Updating silkscreen, changing non-sensitive connector types, swapping non-sensitive components such as decoupling capacitors

Both major and minor hardware versions are accompanied by new hardware project files. Patch hardware versions are applied to the existing hardware project files.

License

Licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.