Freescale Semiconductor M68HC08 manual Software Design, interrupt void pwmISRvoid, Table index =

Software Design

interrupt void pwmISR(void)

Read new (PWM value from table * sineGain)

Increment of table index

Was end of sine tab. reached ?

yes

Table index = 0

no

Increment 500us counter

Has 500us gone ? yes

no

Enable PI ballast stage regulator computing and reset 500us counter

Increment 1ms counter

Has 1ms gone ? yes

Set 1ms flag and reset 1ms counter

no

Reset LDOK to enable new PWM reload and clear reload flag

End of subroutine

Figure 5-5. Flow Chart — Sine Wave Generation Interrupt Routine

Dimmable Light Ballast with Power Factor Correction, Rev. 1

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