MSRS002@ECNCDC.BITNET ("THE DOCTOR.") (06/15/89)
re: Absolute Addresses
Variables are allowed to be given absolute addresses for the
purpose of accessing specific IO addresses. This is highly
system specific, so I wouldn't expect modules using this feature
to be ported from one system to another. Therefore, I would
think you ( the language implementor ) could put whatever was
appropriate for your implementation between the brackets. For
instance, on PC's [0000:0001] would be an appropriate address
form.
IO Ports are sometimes thought of as a separate address space, so
I think [IO0003] might be appropriate. In practice, most
compilers seem to provide separate procedures for dealing with
ports, usually in the system module.
I don't think you would be violating the language, or making it
non-standard if you allowed variables to have addresses in the IO
space.
Tom Ruby
MSRS002@ECNCDC
No disclaimers, I freely admit to my guilt.