UPD78F9500MA-CAC-A Datasheet, PDF (76/342 Pages) Renesas Technology Corp – 8-Bit Single-Chip Microcontrollers

CHAPTER 5 CLOCK GENERATORS
(1) μPD78F920x
Figure 5-1. Block Diagram of Clock Generators (1/2)
Internal bus
Oscillation stabilization
time select register (OSTS)
Preprocessor clock
control register (PPCC)
Processor clock
control register (PCC)
OSTS1 OSTS0
PPCC1 PPCC0
PCC1
X1/P23/ANI3
X2/P22/ANI2
System clock oscillation
stabilization time counter
STOP
System clock
oscillator^Note
Watchdog timer
Crystal/ceramic
oscillation
fX
External clock
input
Prescaler
fX
fX
2
2²
High-speed
internal
oscillation
fXP
fXP
2²
Prescaler
Controller
Low-speed _fRL
internal
oscillator
Clock to peripheral
hardware (fXP)
8-bit timer H1,
watchdog timer
CPU clock
(fCPU)
Option byte
1: Cannot be stopped.
0: Can be stopped.
LSRSTOP
Low-speed internal oscillation
mode register (LSRCM)
Internal bus
Note Select the high-speed internal oscillator, crystal/ceramic oscillator, or external clock input circuit as the
system clock source by using the option byte.
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User’s Manual U18172EJ3V0UD