HD6417660 RENESAS [Renesas Technology Corp], HD6417660 Datasheet - Page 653

• Manufacturer Part Number: HD6417660
• Description: Renesas 32-Bit RISC Microcomputer
• Manufacturer: RENESAS [Renesas Technology Corp]

After it has been initialized by a reset, the RF IC starts outputting a clock signal
(RDI_REFCLK_IN). A counter in the BT power-on-reset/clock-resume control circuit starts
counting the cycles of a clock signal from the RF IC. When the value in the counter matches the
required value, the RF IC is released from the reset state.
The clock signal (RDI_REFCLK_IN) received from the RF IC may be connected to the clock-
pulse generator’s EXTAL pin for use as the LSI’s main clock signal. This may reduce the number
of crystal oscillators required to configure the overall Bluetooth system. In this case, 13 MHz is
the only available main-clock frequency for this LSI, since the frequency on the
RDI_REFCLK_IN pin will be 13 MHz.
An independent clock can be input without connecting the output of the RDI_REFCLK_IN signal
to the EXTAL pin*. In this case, the main clock may run at any frequency within the range
guaranteed for use with this LSI. For details on this range, refer to section 28, Electrical
Characteristics. For details on the EXTAL pin, refer to section 11, Clock Pulse Generator (CPG).
Note: * When the on-chip USBF bus-powered function is used, make sure to input an
independent clock from the RDI_REFCLK_IN input clock and set it to an active state.
Rev. 1.00, 02/04, page 615 of 804