mc68hc708mp16 Freescale Semiconductor, Inc, mc68hc708mp16 Datasheet - Page 139

• Manufacturer Part Number: mc68hc708mp16
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

MC68HC708MP16
Freescale Semiconductor
NOTE:
—
Rev. 3.1
To prevent a partial reload of PWM parameters from occurring while the
software is still calculating them, an interlock bit controlled from software
is provided. This bit informs the PWM module that all the PWM
parameters have been calculated, and it is “okay” to use them. A new
modulus, prescaler, and/or PWM value cannot be loaded into the PWM
module until the LDOK bit in PWM control register 1 is set. When the
LDOK bit is set, these new values are loaded into a second set of
registers and used by the PWM generator at the beginning of the next
PWM reload cycle as shown in
Figure
When the PWM module is enabled (via the PWMEN bit), a load will occur
if the LDOK bit is set. Even if it is not set, an interrupt will occur if the
PWMINT bit is set. To prevent this, the software should clear the
PWMINT bit before enabling the PWM module.
Pulse Width Modulator for Motor Control (PWMMC)
9-10. After these values are loaded, the LDOK bit is cleared.
PWM RELOAD
Figure 9-6. PWM Interrupt Requests
V
DD
Pulse Width Modulator for Motor Control (PWMMC)
D
CK
Figure
LATCH
RESET
9-7,
PWMF
PWMINT
Figure
9-8,
Figure
CPU INTERRUPT
REQUEST
WRITE PWMF AS 0
READ PWMF AS 1,
Technical Data
RESET
OR
9-9, and
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