This stack is a line-at-a-time serial communications stack. In use, it appears like a TTY console, hence the name.
At the "console" card, whatever is typed in the message box followed by a <RETURN> will be sent out the chosen port (including the <RETURN>.) If you want to send a message to HyperCard, do it from any other card, or use <Enter> instead of <RETURN>.
The following help is divided into 2 sections - A brief explanation of the buttons across the top of the console, and then a more technical discussion of the XCMD's and XFCN's used in this stack.