Glossary and Acronyms

Platypus is an odd amalgamation of concepts and components. This may assist comprehension; even my own :P.

This is in alphabetical order, as you might expect.

• ATTENTION pin of the Feature Interconnect: active HIGH, controlled by FM to indicate the FM is ready for interaction.
• Chassis Backplane: The primary circuit board in the enclosure that routes power and data between all the modules via FMI channels, fanning out from the MM connector to all the FMs. This backplane does have traces/pads to accommodate voltage sensing of 3.3 and 5 voltage and high precision low resistance shunts measuring current to monitor power consumption of each FM.
• Chassis Enclosure: The box that holds the stuff.
• cog: in Parallax Propeller 2 parlance, the same as processor/core
• Command Channel (CC): UART serial channel that negotiates and integrates a FM into the system. Every FM connects to a CC.
• Data Channel (DC): SPI serial channel for passing high volume/speed data. MM remains the master, but the clock rate gets negotiated over the CC on initial power up.
• Feature Module Interconnect (FMI): A 12 pin interface between MM and FMs, including power (ground, 3.3 and 5 volts), CC (R/Tx UART), DC (IN/OUT/CLK SPI), /RESET and SLEEP signal from the MM to the FM, and an ATTENTION signal from the FM to the MM.
• Feature Interconnect - Minimal (FIM): potentially, there is a 4 pin bus to accept FM that require only CC and 5V. It may take the physical characteristics of USB-A to make use of available hardware. It may also be compatible with old USB-1.1 devices (think keyboard/mouse), if patent and licensing situation is agreeable. Otherwise, keyboard/mouse may need to live on FM that incorporates a compatibility layer with those devices. Potentially, they're included on a system chassis sort of FM that also drives some LED/status display, etc.
• Feature Module (FM): FMs may be considered as services running on their own processor with their own resources suited to the application. All FMs connect to the MM via a standard 12 pin FMI. They provide additional features to the main system, and may include things like mass storage or database, unique input or display interfaces, internet interface, power management, additional task processors, personal document/time/task management, Geek Port.
• Global Root Path (GRP): The highest path in the GST, essentially "root" of the complete GST.
• Global Service Table (GST): The pseudo-hierarchical list of Service Paths that include a Global Root Path above the MM itself.
• Management Module (MM) : The primary processor that routes the backplane communication and manages the FM access and power.
• Module Manager: Firmware on the Management Module that orchestrates the interactions between all modules. It does not use a standard FMI connection
• Parallax Propeller 2 (P2): The primary processor of the MM central to the system.
• Power Module: Supplies and monitors power to the backplane. It does not use a standard FMI connection.
• /RESET pin of the Feature Interconnect: MM pulls this LOW momentarily to reset the FM, when/if deemed necessary.
• Service Path (SP): a web route-like, or filesystem-like path indicating services and sub-services available on a FM.
• Service Path Parameter Set (SPPS): the set of SP that define entry points to all of the features of a particular FM.
• /SLEEP pin of the Feature Interconnect: MM pulls this LOW to indicate to the FM that the MM will neither request nor respond to activity from the FM and that the FM should put itself to sleep, waking occasionally to see if it should wake again to communicate and process. Just prior to sleeping, it should pull its ATTENTION pin LOW, until it wakes up again and is ready to respond.