screening / glitchy operation - sanity check

[dsc]

Thanks Jonathan, on the scope it looks like the top example from your reply. I can post a scope recording if I figure out how to record with the fancy model I've borrowed from work. The function for the slow ramp is below, coded in C:

void slow_ramp(void)
{
//PWM code for slow ramp start
CCPR1L = 0b00000010; //set to 2, so pulse width is 2 x 16 = 32 with 16 prescaler

while (PR2 != 18) //ramp up speed slowly from 60RPM [PR2 = 77] to 240RPM [PR2 = 18]
{
while (TMR2IF == 0) {} //wait for overflow
PR2--;
__delay_ms(5);
}
}

Using the hardware PWM module on the PIC.

Regards,
dsc.