HD6417727BP160CV Datasheet, PDF (337/1098 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH™ RISC engine Family/ SH7700 Series

Section 11 Extend Clock Pulse Generator for USB (EXCPG)
Section 11 Extend Clock Pulse Generator for USB
(EXCPG)
11.1 Overview
11.1.1 EXCPG
The SH7727 has an on-chip USB interface (USB) which requires a fixed 48-MHz clock source.
The extend clock pulse generator (EXCPG) generates a divided clock from the internal clock (Iφ),
the bus clock (Bφ), or the external clock (UCLK).
Because the clock sources, which can be a candidate to be used by EXCPG, vary from CPG
setting or external clock source, user of SH7727 must adjust the divided clock, carefully to be 48
MHz.
11.2 Functions
11.2.1 Block Diagram
Figure 11.1 shows a block diagram of the EXCPG.
Peripheral clock (Pφ)
Internal clock (Iφ)
Bus clock (Bφ)
External clock (UCLK)
USB clock
(48 MHz)
USB
host
Select
1/1
1/2
USB
1/3
function
Figure 11.1 Block Diagram of EXCPG
Rev.6.00 Mar. 27, 2009 Page 279 of 1036
REJ09B0254-0600