Force Computers SYS68K/CPU-40, Руководство пользователя

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SYS68K/CPU-40/41 FORCE COMPUTERS
H-6
LOCATION MONITOR
A functional module that monitors data transfers over the DTB in order to detect accesses
to the locations it has been assigned to watch. When an access occurs to one of these
assigned locations, the LOCATION MONITOR generates an on-board signal.
MASTER
A functional module that initiates DTB cycles in order to transfer data between itself and
a SLAVE module.
OBO
A SLAVE that sends and receives data 8 bits at a time over D00-D07.
POWER MONITOR MODULE
A functional module that monitors the status of the primary power source to the 1014
system and signals when that power has strayed outside the limits required for reliable
system operation. Since most systems are powered by an AC source, the power monitor
is typically designed to detect drop-out or brown-out conditions on AC lines.
READ CYCLE
A DTB cycle used to transfer 1, 2, or 4 bytes from a SLAVE to a MASTER. The cycle
begins when the MASTER broadcasts and address and an address modifier. Each SLAVE
captures this address and address modifier, and checks to see if it is to respond to the
cycle. If so, it retrieves the data from its internal storage, places it on the data bus, and
acknowledges the transfer. Then the MASTER terminates the cycle.
READ-MODIFY-WRITE CYCLE
A DTB cycle that is used to both read from, and write to a SLAVE location without
permitting any other MASTER to access that location. This cycle is most useful in
multiprocessing systems where certain memory locations are used to control access to
certain systems resources. (For example, semaphore locations.)