
Section 4 Clock Pulse Generator (CPG)
R01UH0025EJ0300 Rev. 3.00
Page 87 of 1336
Sep 24, 2010
SH7261 Group
4.4
Register Descriptions
The clock pulse generator has the following registers.
Table 4.4
Register Configuration
Register Name
Abbreviation R/W
Initial Value Address
Access Size
Frequency control register
FRQCR
R/W
H'1003
H'FFFE0010 16
CKIO control register
CKIOCR
R/W
H'10/H'00
H'FFFE3894 8, 16, 32
4.4.1
Frequency Control Register (FRQCR)
FRQCR is a 16-bit readable/writable register used to specify whether a clock is output from the
CKIO pin in software standby mode, the frequency multiplication ratio of PLL circuit 1, and the
frequency division ratio of the CPU clock and peripheral clock (P
φ). Only word access can be
used on FRQCR.
FRQCR is initialized to H'1003 only by a power-on reset or in deep standby mode. FRQCR retains
its previous value by a manual reset or in software standby mode. The previous value is also
retained when an internal reset is triggered by an overflow of the WDT.
15
14
13
12
11
10
987654321
0
0001000000000011
R
R/W
R
R/W
R
R/W
Bit:
Initial value:
R/W:
———
CKOEN
—
STC[2:0]
—
IFC[2:0]
RNGS
PFC[2:0]
Bit
Bit Name
Initial
Value
R/W
Description
15 to 13
All 0
R
Reserved
These bits are always read as 0. The write value
should always be 0.