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Oscillator sources, Reset circuit – Renesas SH7201 User Manual

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R123

CAN transceiver

0

Connects CAN0_STBn to

microcontroller pin 166

Disconnects CAN0_STBn from

microcontroller pin 166

-

R124

CAN transceiver

0

Connects CAN1_ERRn to

microcontroller pin 174

Disconnects CAN1_ERRn from

microcontroller pin 174

-

R127

CAN transceiver

0

Connects CAN1_STBn to R31

Disconnects CAN0_STBn from R31

R31

R130

Power supply

Connects E8_VCC to the

regulator input

Disconnects E8_VCC from the regulator

input

R102

R134

Interrupt

Connects BUSYn from FLASH

memory chip U3 to microcontroller

IRQ3n

Disconnects BUSYn from FLASH

memory chip U3 from microcontroller

IRQ3n

-

Table 6-5 Option Links

6.7. Oscillator Sources

A crystal oscillator is fitted on the CPU board and used to supply the main clock input to the Renesas microcontroller.

details the

oscillators that are fitted and alternative footprints provided on this CPU board:

Table 6-

Component

Crystal (X1) Fitted 10MHz (HC49/4H package)

Crystal (X2) Fitted 32.768kHz (90SMX package)

Table 6-6: Oscillators / Resonators

Warning: When replacing the default oscillator with that of another frequency, the debugging monitor will not function unless the following

are corrected:

• FDT programming kernels supplied are rebuilt for the new frequency

6.8. Reset Circuit

The CPU Board includes a simple latch circuit that links the mode selection and reset circuit. This circuit is not required on customers’

boards as it is intended for providing easy evaluation of the operating modes of the device on the RSK. Please refer to the hardware

manual for more information on the requirements of the reset circuit.

The reset circuit operates by latching the state of the boot switch (SW1) on pressing the reset button. This control is subsequently used to

modify a port pin state to select which code is executed.

The reset is held in the active state for a fixed period by a pair of resistors and a capacitor. Please check the reset requirements carefully to

ensure the reset circuit on the user’s board meets all the reset timing requirements.

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