A 65K storage unit is actually two sepa-
rate storage units.
Each unit can store
32,768 bytes of information.
Each of these
32K units is the same as described previ-
ously (Figure 2-69).
The units are sepa-
rate physically, and each mounts on a sepa-
rate hinged gate in the 2030 (Figure 2-70).
CPU
Power
Supply
I/o
Power
Connectors
Figure 2-70.
IBM 2030 Showing Two 32K
Storage units
STORAGE CLOCK
•
The M2-I has a separate clock which allows it to operate
independently from the 2030.
•
The clock consists of delay lines and timing latches.
•
The clock is started by either read call or write call
from the 2030.
The M2-I core storage unit contains a tim-
ing generator referred to as the storage
clock.
Having a clock separate from the
2030 clock allows the storage unit to opera-
te independently from the 2030 once the
read call or write call signal starts a
storage cycle.
2-:70
The clock is composed of three 250 nano-
second delay lines tied together with ap-
propriate controls to form a 750 nanosecond
delay line.
The delay line is tapped at 25
nanosecond intervals.
These taps are wired
to a series of latches to produce the com-
posite timing signals required by the
storage unit (Figure 2-71).