Figure 6-36.—Hardwired magnetic ROM.
For ROM operations to take place, the following
3 .l
events generally take place in the following order:
4.
1 .
2.
ROM is either selected on the computer’s front
panel or equivalent of a computer; or the
computer is turned on and it is part of the start
5 .
up routine.
The ROM address is translated.
6.
The ROM address is selected.
The contents of the ROM address are sent to a
designated register for transfer to the instruction
register.
The instruction is sent to the instruction register
for translation.
The instruction is executed.
Figure 6-37.—MOS ROM.
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