SH7751 Group, SH7751R Group
Section 10 Clock Oscillation Circuits
R01UH0457EJ0301 Rev. 3.01
Page 269 of 1128
Sep 24, 2013
10.2
Overview of CPG
10.2.1
Block Diagram of CPG
Figures 10.1(1) and 10.1(2) show a block diagram of the CPG in the SH7751 and SH7751R.
Legend:
FRQCR: Frequency control register
STBCR: Standby control register
STBCR2: Standby control register 2
Oscillator circuit
PLL circuit 1
Frequency
divider 2
Crystal
oscillation
circuit
Frequency
divider 1
PLL circuit 2
CPU clock (Ick)
cycle Icyc
Peripheral module
clock (Pck) cycle
Pcyc
Bus clock (Bck)
cycle Bcyc
CPG control unit
Clock frequency
control circuit
Standby control
circuit
Bus interface
Internal bus
XTAL
EXTAL
MD8
CKIO
MD2
MD1
MD0
FRQCR
STBCR2
×
1
×
1/2
×
1/3
×
1/4
×
1/6
×
1/8
×
6
×
1/2
×
1
STBCR
Figure 10.1 (1) Block Diagram of CPG (SH7751)