[Oberon] Emulating an RS-232 line with the Oberon emulator

[Paul Reed]

>the
> emulator then reads from or writes to them if the program PCLink1 running
> inside the emulator reads from or writes to the memory addresses -56 and
> -52, i.e. the addresses which map the RS-232 line, see RS232.Mod).
>
> So it *should* be possible to extend this mechanism such that the two ends
> are permanently “connected" together. On Mac or Linux, the pipe
> mechanism might be used to accomplish this.

The way PCLink1.Mod is written, the send or receive is always initiated
from the "other" machine, so you would have a chicken-and-egg problem at
present I think.

But the emulator could check for e.g. the presence of a named pipe and use
that for RS232 I/O, set on the command line for the first or both
invocations, and falling back to looking for the presence of those trigger
files.

Then you'd just extend PCLink1 to be able to initiate the conversation.

Don't forget to take into account the zero-length final packet, some idiot
forgot that ;-)

Cheers,
Paul