One line in. One number on the panel.
Take an MCP on a real desk. In Project Magenta Brain you type one line: heading 180. Brain sends it to the unit. The window on the MCP shows 180.
Brain holds the line to the panel. A program can stop and start again, and the panel does not notice. No new connection. No waiting for a port to come free.
If the panel drops, Brain says so, and when. Then it connects again by itself.
A panel is one line in a text file: a name and an address.
Use all of your simulator.
To be continued.