UPD78F1502AGK-GAK-AX Datasheet, PDF (245/1031 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcontrollers

78K0R/Lx3
CHAPTER 5 CLOCK GENERATOR
Notes 1.
2.
3.
4.
The internal reset processing time includes the oscillation accuracy stabilization time of the internal high-
speed oscillation clock.
When releasing a reset, confirm the oscillation stabilization time for the X1 clock using the oscillation
stabilization time counter status register (OSTC).
The microcontroller operates on the 8 MHz internal high-speed oscillation clock if 8 MHz or 20 MHz is
selected for the internal high-speed oscillator by using the option byte or on the 1 MHz internal high-speed
oscillation clock if 1 MHz is selected.
If the internal high-speed oscillator is set to 1 MHz by using the option byte, the 20 MHz internal high-speed
oscillation clock cannot be used.
Cautions 1. If the voltage rises with a slope of less than 0.5 V/ms (MIN.) from power application until the
voltage reaches 1.8 V, input a low level to the RESET pin from power application until the voltage
reaches 1.8 V, or set the LVI default start function stopped by using the option byte (LVIOFF = 0)
(see Figure 5-14). By doing so, the CPU operates with the same timing as <2> and thereafter in
Figure 5-13 after reset release by the RESET pin.
2. It is not necessary to wait for the oscillation stabilization time when an external clock input from
the EXCLK pin is used.
R01UH0004EJ0501 Rev.5.01
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Jun 20, 2011