Renesas Single-Chip Microcomputer SH7203 Información técnica descargar pdf (Pagina 22)

Chapter 7. Modes

This CPU board supports four clock modes. Please refer to Table 7-1 for clock mode selection.

SW4-9 (CPU Pin 96, MD_CLK1) SW4-8 (CPU Pin 97, MD_CLK0) Clock Mode

ON ON 0

ON OFF 1

OFF ON 2

OFF OFF 3

Table 7-1 Clock Mode Selection

a. Clock Mode 0 – This is the default mode on RSK+SH7203. In mode 0, clock is input from the EXTAL pin or the crystal

oscillator. The PLL circuit shapes waveforms and the frequency is multiplied according to the frequency control register setting

before the clock is supplied to the LSI. The oscillating frequency for the crystal resonator and EXTAL pin input clock ranges

from 10 to 16.67 MHz. The frequency range of CKIO is from 40 to 66.67 MHz.

Clock Mode 1 - In mode 1, clock is input from the EXTAL pin or the crystal oscillator. The PLL circuit shapes waveform and

the frequency is multiplied according to the frequency control register setting before the clock is supplied to the LSI. The

oscillating frequency for the crystal resonator and EXTAL pin input clock ranges from 20 to 33.33 MHz. The frequency range of

CKIO is from 40 to 66.67 MHz.

Clock Mode 2 - In mode 2, the CKIO pin functions as an input pin and draws an external clock signal. The PLL circuit shapes

waveform and the frequency is multiplied according to the frequency control register setting before the clock is supplied to the

LSI. The frequency range of CKIO is from 40 to 66.67 MHz.

Clock Mode 3 - In mode 3, clock is input from the USB_X1 pin or the crystal oscillator. The external clock is input through this

pin and waveform is shaped in the PLL circuit. Then the frequency is multiplied according to the frequency control register

setting before the clock is supplied to the LSI. The frequency of CKIO is the same as that of the input clock (USB_X1/crystal

resonator) (48 MHz).

Warning - While changing the clock mode please ensure that correct Frequency Multiplication/division Ratios are set in the FRQCR

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Renesas Single-Chip Microcomputer SH7203 Información técnica Pagina 22