IBM System/23 Datamaster: Difference between revisions
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Regarding the system clock, it is derivated from a 18.432MHz square wave oscillator which is then divided by three to feed the microprocessor with a 6.14MHz signal.
It has been found by continuity tests that the SID signal from the CPU is tied to the 5V supply rail. The microprocessor checks its value during test 1 at power-up.
=== ROM Operating System ===
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