Modelling internal vs. external connectors (solved)

[Jochen Wendebaum]

I am currently modelling a system consisting of several hardware units and have come to the following issue and am wondering how to model the following two setups properly:

I have two devices, 1 and 2.
The internal PCB has two connectors, C01 and C02.
On Device 1, it is mounted in a way that the connectors are accessible from the outside, becoming the external connectos X1 and X2.
On Device 2, it is mounted internally, and C01 is through a cable connected to X1, C02 is cabled to X2.

How do I model Device 1 properly?

[qwerty]

The 2nd looks more appropriate, but you should probably look into SysML.

q.

[Jochen Wendebaum]

My question is how to correctly model the first device in SysML, where the external connectors and the internal on the PCB are the same component.

Should I have C01 and C02 as Proxy Ports?

[qwerty]

Oh, didn't see the block. My age, my eyes...

q.

P.S. there's a recent thread about proxy here

[Jochen Wendebaum]

Still, is it really a proxy? Both X1 and C01 are components, but in different contexts, C01 exists on the PCB context, X1 on the device context.
Somehow I don't see how any of them could be a proxy, but I might be wrong.

[qwerty]

I meant this one:
https://sparxsystems.com/forums/smf/index.php/topic,48393.msg280850.html#msg280850

q.

[tweber]

The ports on PCBA are behavioral ports.  They are connected to the delegate ports on the housing by connectors. Those delegate ports are then connected externally by connectors to other devices.  This concept is supported both in UML and SysML. 

[Takeshi K]

Hello Jochen,

This is just my idea and I am afraid it might be wrong.

I think it depends on what you want to describe as a model, especially which view you want to describe. There are two views, one is logical and the other is physical.

In the logical view, Device1 and Device2 are the same and I will choose the 'Device2' IBD. In both devices, port X1 is connected to port C1. (In the logical model, I do not care about the length of the cable between the ports. In Device1, the length of the cable between the ports is just 0).

In the following image, the left half is my logical model for both Device1 and Device2.

https://www.sparxsystems.jp/temp/devices.png

In the physical view, we need to distinguish these two Devices. I will describe the IBD of Device1 as shown in the image above, right side. This is because Device1 itself has the C01 port. The Device2 model is the same as yours.

HTH,


 

[Jochen Wendebaum]

Hi Takeshi,

that makes a lot of sense, thank you for your help and effort!

Jochen