How can I assign an input pin?

Hi Andrew,

Sorry for misunderstanding. What I'm going to do is:

1. Input an singal, from a function generator, into the MCU.
2. Use this signal to trigger, with rising edge, the MCU to output data.
For example,
Input a 1M signal into the MCU, and the MCU outputs data bit by bit with the frequency 1M(every 1/1M sencond outputs a bit)

I can't use for function, because the machine cycle is too slow, which is only 270k.
I'd like to output the signal in 1MHz.

Thanks a lot!

Hi Andrew,

Sorry for misunderstanding. What I'm going to do is:

1. Input an singal, from a function generator, into the MCU.
2. Use this signal to trigger, with rising edge, the MCU to output data.
For example,
Input a 1M signal into the MCU, and the MCU outputs data bit by bit with the frequency 1M(every 1/1M sencond outputs a bit)

I can't use for function, because the machine cycle is too slow, which is only 270k.
I'd like to output the signal in 1MHz.

Thanks a lot!

Hi,

I'm trying not using "interrupt" but inputting an external signal for trigger.
2 ways for solving the problem. See if anyone can help. Thanks for your time.

So why on earth are you running it so slowly??!!

Clearly, you have no chance of doing anything at 1MHz when the chip is running so slowly!!