Renesas Renasas Single-Chip Microcomputer SH7086 Uživatelský manuál stáhnout pdf (Strana 15)

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.

Table 6-10: Oscillators / Resonators details the oscillators that are fitted and alternative footprints provided on this CPU board:

Component

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

Table 6-10: 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 provides an easy method for swapping

the device between Boot Mode and User mode. 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.

1 2 ... 10 11 12 13 14 15 16 17 18 19 20 ... 30 31

Žádné komentáře

Renesas Renasas Single-Chip Microcomputer SH7086 Uživatelský manuál Strana 15