MC9S12E128CPV Freescale Semiconductor, MC9S12E128CPV Datasheet - Page 411

• Manufacturer Part Number: MC9S12E128CPV
• Description: Microcontrollers (MCU) 16 Bit 16MHz
• Manufacturer: Freescale Semiconductor

Specifications of MC9S12E128CPV

• Data Bus Width: 16 bit
• Program Memory Type: Flash
• Program Memory Size: 128 KB
• Data Ram Size: 8 KB
• Interface Type: SCI, SPI
• Maximum Clock Frequency: 25 MHz
• Number Of Programmable I/os: 92
• Number Of Timers: 16 bit
• Operating Supply Voltage: 3.135 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: LQFP-112
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit
• On-chip Dac: 8 bit, 2 Channel
• Lead Free Status / Rohs Status: No RoHS Version Available

To calculate the output frequency in center aligned output mode for a particular channel, take the selected
clock source frequency for the channel (A, B, SA, or SB) and divide it by twice the value in the period
register for that channel.
As an example of a center aligned output, consider the following case:
Shown below is the output waveform generated.
12.4.2.7
The PWM timer also has the option of generating 6-channels of 8-bits or 3-channels of 16-bits for greater
PWM resolution}. This 16-bit channel option is achieved through the concatenation of two 8-bit channels.
The PWMCTL register contains three control bits, each of which is used to concatenate a pair of PWM
channels into one 16-bit channel. Channels 4 and 5 are concatenated with the CON45 bit, channels 2 and 3
are concatenated with the CON23 bit, and channels 0 and 1 are concatenated with the CON01 bit.
When channels 4 and 5 are concatenated, channel 4 registers become the high-order bytes of the double
byte channel as shown in
registers become the high-order bytes of the double byte channel. When channels 0 and 1 are concatenated,
channel 0 registers become the high-order bytes of the double byte channel.
Freescale Semiconductor
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•
E = 100 ns
PWMx frequency = clock (A, B, SA, or SB) / (2*PWMPERx)
PWMx duty cycle (high time as a% of period):
— Polarity = 0 (PPOLx = 0)
— Polarity = 1 (PPOLx = 1)
Clock source = bus clock, where bus clock = 10 MHz (100 ns period)
PPOLx = 0
PWMPERx = 4
PWMDTYx = 1
PWMx frequency = 10 MHz/8 = 1.25 MHz
PWMx period = 800 ns
PWMx duty cycle = 3/4 *100% = 75%
Duty cycle = [(PWMPERx-PWMDTYx)/PWMPERx] * 100%
Duty cycle = [PWMDTYx / PWMPERx] * 100%
PWM 16-Bit Functions
Change these bits only when both corresponding channels are disabled.
Figure 12-39. PWM Center Aligned Output Example Waveform
Figure
12-40. Similarly, when channels 2 and 3 are concatenated, channel 2
MC9S12E128 Data Sheet, Rev. 1.07
DUTY CYCLE = 75%
PERIOD = 800 ns
NOTE
Chapter 12 Pulse-Width Modulator (PWM8B6CV1)
E = 100 ns
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