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Reset circuit – Renesas Single-Chip Microcomputer H8/36079 User Manual

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oscillators that are fitted and alternative footprints provided on this RSK

:

Component

Crystal (X1)

Fitted

32.768 KHz (90SMX package)

Crystal (X2)

Fitted

20 MHz (HC49/4H package)

Table 6-6: Oscillators / Resonators

6.8. Reset Circuit

The CPU Board includes a simple latch circuit that links the mode selection and reset circuit. This provides an easy method for swapping

the device between Boot Mode and User mode. This circuit is not required on customer’s 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 on pressing the reset button. This control is subsequently used to

modify the port pin P24 states as required.

The port pin P24 must change state only while the reset signal is active to avoid possible device damage.

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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