[Oberon] Other CONST.

[Paul Reed]

Hi Lyall,

> MODULE Clipboard in Peter De Wachter's emulator has
> CONST control = -24; data = -20;

They are memory-mapped input/output addresses.  Normally, see the last
page of

https://www.inf.ethz.ch/personal/wirth/FPGA-relatedWork/RISC-Arch.pdf

but since -24 and -20 (0FFFFFFE8H and FFFFFFECH) are defined by the
emulator presumably for virtual machine to host clipboard purposes, you
don't see those particular addresses in Prof. Wirth's document.

HTH,
Paul