Date post: | 29-Dec-2015 |
Category: |
Documents |
Upload: | jesse-craig |
View: | 224 times |
Download: | 2 times |
WHAT IS COVERED AND WHAT IS NOT• Cover:
• Count down mode and basic configuration to get the motor run.
• Not cover:
• Count up/down mode
• Dead band
• Interrupt
• Others
LOAD: Determines PWM period based on system clock
ADown/BDown: determine pulsewidthCOMPA/COMPB: we set the value to get Adown/BDown
ILLUSTRATION• Example: System clock is 80[Mhz] (can be reduced).
• PWM Clock will be:
• 80[Mhz]/64=1.25[Mhz] (period is 0.8 [us])
• We want:
• 2[ms] period. What is the Load value?
• Answer: LOAD= (2[ms]/0.8[us])-1
ILLUSTRATION• Now we need to generate pulse width,
• We will generate 20% duty cycle for PWMA for this example
• HOW?
• Easy: LOAD is 100%, so 20%*LOAD is the value for COMPA.
SUMMARY OF THE CODE:
• Initialize and enable the Clocks
• Enable the PWM Modules
• Configure Pin types
• Set Duty Cycle
• Enable the gate
• Enable generators