IBD: Arduino Mega2560R3 - headers with pins and logical ports

The Internal Block Diagram (IBD) shows the 3 main headers with all «pin» Ports and all nested logical contract Ports, as well as ICSP headers for each of the ATmega2560 and ATmega16U2 chips, in the context of the Arduino Mega2560R3 board.

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MagicDraw/Cameo supports embedding images in diagrams

No specific connections are shown (yet), we'll see those in dedicated smaller diagrams according to function groups and (where appropriate) also with the chip pins. One can however see for many pins as Context-Specific Values (in the not so ideally named initialValues compartment) the pin mappings to the main ATmega2560 mcu chip and the ATmega16U2 chip (used for USB-to-TTL), as gleaned from the official Arduino pinout diagrams.

The nested logical contract Ports show where specific "logical" connections could be made to represent use of specific functionality for pins with overloaded functionality (as would usually be driven by Arduino library commands for a specific application). These won't be used further in this trail.

This tool feature was used again:

In MagicDraw/Cameo an assigned stereotype of a Classifier that types an instance-like element (such as a part Property) "shines through" unless it has an instance-level stereotype assigned. This is sometimes called a "secondary stereotype".

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IBD: ATmega2560 with pin Ports in context of Arduino Mega2560R3

Notes

[CAPABILITY, FEATURE, TIP, TOOL] In MagicDraw/Cameo an assigned stereotype of a Classifier that types an instance-like element (such as a part Property) "shines through" unless it has an instance-level stereotype assigned. This is sometimes called a "secondary stereotype".

[NAMING, POLICY, STYLE]{STRONG} SysML: Webel: "Trust the Type!" - Often the name of the Type of an anonymous Property or instance-level element is completely sufficient to indicate its role - unless multiple Properties of the same Type have different roles within the same owner context!

[NAMING, POLICY, STYLE] "Trust the Port or Pin Type!" - Often the name of the Type of an anonymous Port or Pin is completely sufficient to indicate its role, unless a clear indication of its direction or unique role is required.

[ASSERTION, NAMING, WARNING] The SysML block compartment name 'initialValues' for what are really "context-specific values" is confusing - even completely misleading; please just think of them as 'contextValues' (and initial values as a special context case)

[CAPABILITY, FEATURE, TOOL]{INFORMATIVE} MagicDraw/Cameo supports embedding images in diagrams

Snippets (quotes/extracts)

[SysML-1.6] A compartment with a label of “initialValues” may be used to show values of properties belonging to a containing block. These values override any default values that may have been previously specified on these properties on their originally defining block