ZiLOG System 8000 User Manual page 54

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Zilog
USER
Indirect Register (IR) addressing mode
input
interrupt
In this mode, the operand address is
contained within a register.
Information taken from the terminal or
from files is called input. Commands
normally read input from their standard
input which is, by default, the termi-
nal. The metacharacter followed by a
file name can be used to cause input to
be read from a file. Many commands also
read .from a file specified as argument.
Commands placed in pipelines are read
from the output of the previous command
in the pipeline. The leftmost command
in a pipeline reads from the terminal if
its input is not redirected and if a
file name is not given to use as stan-
dard input. (See pipeline.)
An interrupt is a signal that causes
most programs to stop execution. It is
generated by pressing the RUB key. Cer-
tain programs such as C shell and the
editors handle an interrupt in special
ways, usually by stopping what they are
doing and prompting for another command.
interrupt request
An event other than a trap or jump or
call instruction that changes the normal
flow of instruction execution. (See
nonmaskable interrupts.)
interrupt service routine
The routine executed in response to an
interrupt.
interrupt/trap acknowledge transaction
The transaction initiated by the CPU in
response to an interrupt or trap.
Obtains an identifier word from the
interrupting device or memory management
hardware.
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