ZiLOG System 8000 User Manual page 55

USER
I
~~
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I/O address
Zilog USER
The address of an I/O port, always 16
bits long. Word por~s may have even or
odd addresses, Special I/O byte ports
are even, and Standard I/O byte ports
are odd.
I/O transaction
Kernel
A transaction that transfers data to or
from a peripheral device or memory
management hardware.
The system software task -that manages
task scheduling and intercommunication
for the Zilog S8000 system. The Kernel
provides process management, file
management, and input/output (I/O) pro-
cessing.
logical address
.login
logout
• logout
long word
The address manipulated by the program-
mer; used by instructions and output by
the Z8001.
The file .login in the user's
~
directory
1S
read by the C shell each
time the user logs in to ZEUS; the com-
mands there are executed.
The logout command causes a login shell
to exit. Normally, a login shell exits
when control-d is pressed, generating an
end-of-file (EOF) •
When a user logs off of ZEUS, the shell
prints .logout and executes commands
from the file .logout in the user's ~
directory.
A long word is 32 contiguous bits; a
long word in memory starts on an even
addressable byte boundary~
memory address An address specifying a location in
memory. Word and long-word addresses
must be even, byte addresses may be even
or odd.
Zilog
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