83
3.6 Gear Control Register (GCR)
[bit 12] DBLON
This bit specifies the clock doubler operation mode. This bit is initialized by resetting. This
model does not support the clock doubler function.
[bit 11, 10] PCK1, 0
These bits specify the gear cycle of peripherals. These bits, and the cycles selected by the
bits, have the relationships shown in Table 3.6.2. These bits are initialized by resetting.
When the CPU clock frequency is higher than 25 MHz, set the peripheral clock frequency to
less than half of the CPU clock frequency.
The maximum peripheral clock frequency is 25 MHz.
<Note>
To change both the CPU and peripheral gears, temporarily set both systems to the same gear
and then set each system to a desired gear.
When the gear settings of both CPU and peripherals are the same before changing, or the gear
of only one side will be changed, or when both will be set to the same gear, the gear(s) can be
set directly to the desired value.
DBLAK
Internal : external operating frequency
0
Operating at 1:1 [Initial value]
1
Operating at 2:1
DBLON
Internal : external operating frequency
0
Operating at 1:1 [Initial value]
1
Operating at 2:1
Table 3.6-2 Peripheral Machine Clock
PCK1
PCK0
CHC
Peripheral machine clock
(source oscillation: input frequency from X0)
0
0
0
PLL
× 1
0
1
0
PLL
× 1/
2
1
0
0
PLL
× 1/4
1
1
0
PLL
×
1/8
0
0
1
Source oscillation
×
1/2
0
1
1
Source oscillation
×
1/2
×
1/2
1
0
1
Source oscillation
×
1/2
×
1/4
1
1
1
Source oscillation
×
1/2
×
1/8 [Initial value]
PLL: PLL oscillation frequency
Source oscillation: Input frequency from X0
Summary of Contents for MB91F109
Page 2: ......
Page 3: ...FUJITSU LIMITED FR30 32 Bit Microcontroller MB91F109 Hardware Manual ...
Page 4: ......
Page 10: ...vi ...
Page 24: ...xx ...
Page 96: ...72 CHAPTER 2 CPU ...
Page 224: ...200 CHAPTER 4 BUS INTERFACE ...
Page 234: ...210 CHAPTER 5 I O PORTS ...
Page 268: ...244 CHAPTER 9 U TIMER ...
Page 290: ...266 CHAPTER 10 UART ...
Page 314: ...290 CHAPTER 12 16 BIT RELOAD TIMER ...
Page 322: ...298 CHAPTER 13 BIT SEARCH MODULE ...
Page 392: ...368 CHAPTER 16 FLASH MEMORY ...
Page 432: ...408 APPENDIX E Instructions F Table E 2 Instruction Formats OP rel11 5 11 ...
Page 448: ...424 APPENDIX E Instructions ...
Page 449: ...425 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Page 458: ...434 INDEX ...
Page 460: ......
Page 461: ...FUJITSU SEMICONDUCTOR FR30 32 Bit Microcontroller MB91F109 Hardware Manual ...