I am using Timer1 on an Atmega32 to generate an output clock of 9.216MHz (sysclk = 18.432MHz) which will feed some other IC's. I generate the clock in CTC mode, and having the mega toggle the output compare every two cycles (OCR1A = 0). The output passes through a 1K/2K resistor divider to bring it down to 3.3v.
The output of this setup is right on a 9.216MHz, but the slew rate on the waveform is [wrong] intriguing... ;)
Is it my resistor divider that is killing the slew rate on the clock? It works anyways, but I would prefer having a proper waveform if at all possible...
P.S. The scope measurements were taken right after the divider, no load connected to the output..
Config Pind.5 = Output ' OC1A pin as output Ocr1ah = &H00 : Ocr1al = &H00 ' Set output compare register to output a 9.216MHz clock Tccr1a = &B01000000 : Tccr1b = &B00001001 ' Configure Timer1 as CTC with output compare toggle