R5F211B2DSP datasheet(80/339 Pages) RENESAS

80 / 339 page

R8C/1A Group, R8C/1B Group

10. Clock Generation Circuit

Rev.1.30

Dec 08, 2006

Page 64 of 315

REJ09B0252-0130

Figure 10.6

Registers HRA1 and HRA2

High-Speed On-Chip Oscillator Control Register 1

(1)

Symbol

Address

After Reset

HRA1

0021h

When Shipping

NOTE :

2. Adjust the HRA1 register so that the frequency of the high-speed on-chip oscillator w ill be the maximum value or

less of the system clock.

b7 b6 b5 b4 b3 b2 b1 b0

Set the PRC0 bit in the PRCR register to 1 (w rite enable) before rew riting the HRA1 register.

Function

The frequency of the high-speed on-chip oscillator is adjusted w ith bits 0 to 7.(2)

High-speed on-chip oscillator frequency = 8 MHz

(HRA1 register = value w hen shipping ; fRING-fast mode 0)

Setting the HRA1 register to a low er value (minimum value: 00h), results in a higher

frequency.

Setting the HRA1 register to a higher value (maximum value: FFh), results in a low er

frequency.

High-Speed On-Chip Oscillator Control Register 2

(1)

Symbol

A ddress

A f ter Reset

HRA 2

0022h

00h

Bit Symbol

Bit Name

Function

NOTES :

1. Set the PRC0 bit in the PRCR register to 1 (w rite enable) bef ore rew riting the HRA 2 register.

5. Set the HRA 20 and HRA 21 bits so that the f requency of the high-speed on-chip oscillator w ill be the maximum value

or less of the system clock.

b7 b6 b5 b4 b3 b2 b1 b0

000

HRA 20

HRA 21

High-speed on-chip oscillator mode

select bits(5)

b1 b0

0 0 : f RING-f ast mode 0(2)

0 1 : f RING-f ast mode 1(3)

1 0 : f RING-f ast mode 2(4)

1 1 : Do not set.

High-speed on-chip oscillator f requency = 8 MHz (HRA 1 register = value w hen shipping)

If f RING-f ast mode 0 is sw itched to f RING-f ast mode 1, the f requency is multiplied by 1.5.

If f RING-f ast mode 0 is sw itched to f RING-f ast mode 2, the f requency is multiplied by 0.5.

—

(b4-b2)

Reserved bits

Set to 0.

—

(b7-b5)

—

Nothing is assigned. If necessary, set to 0.

When read, the content is 0.

R5F211B2DSP Datasheet(PDF) 80 Page - Renesas Technology Corp

R5F211B2DSP Datasheet(HTML) 80 Page - Renesas Technology Corp

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL