Tool/software: Code Composer Studio
I need a sanity check here. I'm using the TM4C123G Launchpad. I have the clock set at 80Mhz.
SysCtlClockSet(SYSCTL_SYSDIV_2_5 | SYSCTL_USE_PLL | SYSCTL_OSC_MAIN | SYSCTL_XTAL_16MHZ);
If I understand correctly, the PLL runs at 200MHz, so 200/2.5 = 80MHz clock
I have a GPIO connected to the o-scope. I'm turning it on and off immediately.
GPIOPinWrite(GPIO_PORTA_BASE, GPIO_PIN_3, GPIO_PIN_3);
GPIOPinWrite(GPIO_PORTA_BASE, GPIO_PIN_3, 0);
The time from the rising edge of the GPIO to the falling edge of the GPIO is measured at about 148 ns. With an 80Mhz clock, this seems a little on the slow side to me. Am I screwing up the math or something?