C8051F52X Datasheet, PDF (191/220 Pages) Silicon Laboratories – 8/4/2 kB ISP Flash MCU Family

C8051F52x-53x
SFR Definition 19.3. CKCON: Clock Control
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset Value
—
—
T2MH T2ML
T1M
T0M
SCA1
SCA0 00000000
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
SFR Address: 0x8E
Bit7–6: RESERVED. Read = 0b; Must write 0b.
Bit5: T2MH: Timer 2 High Byte Clock Select.
This bit selects the clock supplied to the Timer 2 high byte if Timer 2 is configured in split 8-
bit timer mode. T2MH is ignored if Timer 2 is in any other mode.
0: Timer 2 high byte uses the clock defined by the T2XCLK bit in TMR2CN.
1: Timer 2 high byte uses the system clock.
Bit4: T2ML: Timer 2 Low Byte Clock Select.
This bit selects the clock supplied to Timer 2. If Timer 2 is configured in split 8-bit timer
mode, this bit selects the clock supplied to the lower 8-bit timer.
0: Timer 2 low byte uses the clock defined by the T2XCLK bit in TMR2CN.
1: Timer 2 low byte uses the system clock.
Bit3: T1M: Timer 1 Clock Select.
This select the clock source supplied to Timer 1. T1M is ignored when C/T1 is set to logic 1.
0: Timer 1 uses the clock defined by the prescale bits, SCA1–SCA0.
1: Timer 1 uses the system clock.
Bit2: T0M: Timer 0 Clock Select.
This bit selects the clock source supplied to Timer 0. T0M is ignored when C/T0 is set to
logic 1.
0: Counter/Timer 0 uses the clock defined by the prescale bits, SCA1–SCA0.
1: Counter/Timer 0 uses the system clock.
Bits1–0: SCA1–SCA0: Timer 0/1 Prescale Bits.
These bits control the division of the clock supplied to Timer 0 and Timer 1 if configured to
use prescaled clock inputs.
SCA1 SCA0
Prescaled Clock
0
0
System clock divided by 12
0
1
System clock divided by 4
1
0
System clock divided by 48
1
1
External clock divided by 8
Note: External clock divided by 8 is synchronized with
the system clock.
Rev. 0.3
191