mc9s12e256 Freescale Semiconductor, Inc, mc9s12e256 Datasheet - Page 386

• Manufacturer Part Number: mc9s12e256
• Description: Hcs12 Microcontrollers 16-bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Chapter 12 Pulse-Width Modulator (PWM8B6CV1)
12.3.2.4
This register selects the prescale clock source for clocks A and B independently.
Read: anytime
Write: anytime
386
PCKB[2:0]
PCKA[2:0]
PCLK2
PCLK1
PCLK0
Reset
Field
Field
6:5
2:0
2
1
0
W
R
Pulse Width Channel 2 Clock Select
0 Clock B is the clock source for PWM channel 2.
1 Clock SB is the clock source for PWM channel 2.
Pulse Width Channel 1 Clock Select
0 Clock A is the clock source for PWM channel 1.
1 Clock SA is the clock source for PWM channel 1.
Pulse Width Channel 0 Clock Select
0 Clock A is the clock source for PWM channel 0.
1 Clock SA is the clock source for PWM channel 0.
Prescaler Select for Clock B — Clock B is 1 of two clock sources which can be used for channels 2 or 3. These
three bits determine the rate of clock B, as shown in
Prescaler Select for Clock A — Clock A is 1 of two clock sources which can be used for channels 0, 1, 4, or 5.
These three bits determine the rate of clock A, as shown in
PWM Prescale Clock Select Register (PWMPRCLK)
0
0
7
PCKB2–PCKB0 and PCKA2–PCKA0 register bits can be written anytime.
If the clock prescale is changed while a PWM signal is being generated, a
truncated or stretched pulse can occur during the transition.
Figure 12-6. PWM Prescaler Clock Select Register (PWMPRCLK)
= Unimplemented or Reserved
PCKB2
0
6
Table 12-4. PWMCLK Field Descriptions (continued)
Table 12-5. PWMPRCLK Field Descriptions
PCKB1
MC9S12E256 Data Sheet, Rev. 1.08
0
5
PCKB0
NOTE
0
4
Description
Description
Table
12-6.
Table
3
0
0
12-7.
PCKA2
0
2
PCKA1
Freescale Semiconductor
0
1
PCKA0
0
0