Hi,

Does anyone have experience with the Power Control PWM module on the 
18F4331 or it's siblings?

I have a glitch on the start of the PWM pulse train after switching from 
one half-cycle to the next using the Output Override bits (independent 
mode).

I've isolated the problem to the following C code;

InCycle = !InCycle; // toggle negative to positive etc.

switch(InCycle)
 {
    case POSITIVE:   POVD0 = 0; // PWM0 disabled
                                 NOP();
                                 POVD1 = 1; // PWM1 enabled
                                 break; 
    case NEGATIVE: POVD1 = 0; // PWM1 disabled
                                 NOP();
                                 POVD0 = 1; // PWM0 enabled
                                 break; 
 }

PWM0 controls one diagonal pair of an H-Bridge IGBT module and PWM1 the 
other pair.

If I comment-out the above code no glitch appears.

I've tried manipulating UDIS and PTEN bits and adding delays where the 
above NOPs appear but without success.

Thanks in advance.

Nigel

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