I'm trying to interface an OV5642 camera module to a T3.6. I'm not getting the response at the I2C address shown in the data sheet but another, 0x3C. It may be due to the XCLK signal running at too low a frequency. The data sheet often refers to a frequency of 24MHz but I can't come anywhere close to that using the timer. The highest it will go is 1MHz using an argument of 1(usec).

Question:
Can this library function be made to run at a higher frequency?

Is there a better way of getting the T3.6 to supply the signal?

Is an external crystal controlled oscillator the more reasonable choice?