Figure 6-5.—Memory address with an 8-bit word.
Logic that evaluates priorities of memory
requests
Logic that selects read/write operations
Interface logic that acknowledges reading data
from memory and generates enables that write
data into memory
Timing Circuits
The timing circuits provide the enables to manage
the control circuits of the memory cycle—read and/or
write. For some computers, this means use of the
computer’s master clock and one or two other timing
signals derived from the master clock to control the flow
of data in memory. Microcomputers are an example of
this. In more complex computers, each of the
functional areas has its own master clock and timing
circuits. Memory timing is usually initiated only when
a read/write operation has been requested or selected.
Some
are as
of the more common uses of the timing circuits
follows:
To initiate read and/or write operations
To clear registers used for read/write operations
To enable selection of memory address using
selectors and translators
To enable and strobe or gate memory address and
data into registers used for read/write operations
6-5
