NEC MuPD78F0132H, Руководство пользователя

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CHAPTER 5 CLOCK GENERATOR
User’s Manual U16899EJ2V0UD
111
5.3 Registers Controlling Clock Generator
The following six registers are used to control the clock generator.
•
Processor clock control register (PCC)
•
Ring-OSC mode register (RCM)
•
Main clock mode register (MCM)
•
Main OSC control register (MOC)
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Oscillation stabilization time counter status register (OSTC)
•
Oscillation stabilization time select register (OSTS)
(1) Processor clock control register (PCC)
The PCC register is used to select the CPU clock, the division ratio, main system clock oscillator operation/stop
and whether to use the on-chip feedback resistor
Note
of the subsystem clock oscillator.
The PCC is set by a 1-bit or 8-bit memory manipulation instruction.
RESET input clears PCC to 00H.
Note The feedback resistor is required to control the bias point of the oscillation waveform so that the bias point
is in the middle of the power supply voltage (see Figure 5-11 Subsystem Clock Feedback Resistor).