
R8C/3GM Group
9. Clock Generation Circuit
R01UH0284EJ0100 Rev.1.00
Aug 09, 2011
9.2.10
High-Speed On-Chip Oscillator Control Register 4 (FRA4)
9.2.11
High-Speed On-Chip Oscillator Control Register 5 (FRA5)
9.2.12
High-Speed On-Chip Oscillator Control Register 6 (FRA6)
9.2.13
High-Speed On-Chip Oscillator Control Register 3 (FRA3)
Set the PRC0 bit in the PRCR register to 1 (write enabled) before rewriting the FRA3 register.
Also, rewrite the FRA3 register when the FRA00 bit in the FRA0 register is set 0 (high-speed on-chip oscillator
off).
Address 0029h
Bit
b7b6b5
b4b3b2
b1b0
Symbol
——
———
After Reset
When shipping
Bit
Function
R/W
b7-b0 36.864 MHz frequency correction data is stored.
The frequency can be adjusted by transferring this value to the FRA1 register and by
transferring the correction value in the FRA5 register to the FRA3 register.
R
Address 002Ah
Bit
b7b6b5
b4b3b2
b1b0
Symbol
——
———
After Reset
When shipping
Bit
Function
R/W
b7-b0 36.864 MHz frequency correction data is stored.
The frequency can be adjusted by transferring this value to the FRA3 register and by
transferring the correction value in the FRA4 register to the FRA1 register.
R
Address 002Bh
Bit
b7b6b5
b4b3b2
b1b0
Symbol
——
———
After Reset
When shipping
Bit
Function
R/W
b7-b0 32 MHz frequency correction data is stored.
The frequency can be adjusted by transferring this value to the FRA1 register and by
transferring the correction value in the FRA7 register to the FRA3 register.
R
Address 002Fh
Bit
b7b6b5
b4b3b2
b1b0
Symbol
——
———
After Reset
When shipping
Bit
Function
R/W
b7-b0 The frequency of the high-speed on-chip oscillator can be adjusted by setting as follows:
40 MHz:
FRA1 = value after reset, FRA3 = value after reset
36.864 MHz: Transfer the value in the FRA4 register to the FRA1 register and the value in
the FRA5 register to the FRA3 register.
32 MHz:
Transfer the value in the FRA6 register to the FRA1 register and the value in
the FRA7 register to the FRA3 register.
R/W