1ms Delay function or Similar help

[Apaseo 3]

Hello,

I was wondering if someone could help me create or find a delay function.

 

I was thinking a 1ms delay function could work.

 

I would like to have this, so that I can have some timed prompts on an LCD that I have working.

 

Below is a fraction of my main.c 

I hope you guys can help me.

  main(){
  LcdClrDisp();
  LcdMoveCursor(1,4);
  LcdDispStrg("It is");
//-->Delay Function Here
  LcdClrDisp();
  LcdMoveCursor(2,4);
  LcdDispStrg("Working :)");
//-->Delay Function Here
    }

Thanks

[chicken 630]

_delay_cycles(), at least when working with CCS, might do the job.

 

As it counts cycles, it's dependent on the CPU clock. For milliseconds, it would look something like this:

_delay_cycles(MCU_clock_in_Hz / 1000 * wait_time_in_ms);

[Apaseo 3]

I have been using that, but it is not very accurate.

 

Here is what I was using:

	BCSCTL1 |= DIVA_3;				// ACLK/8
	BCSCTL3 |= XCAP_3;

	BCSCTL1 = CAL_BC1_1MHZ;		// Set DCO to 1MHz
	DCOCTL = CAL_DCO_1MHZ;

Having the external crystal installed, along witht this code would create a 1ms delay when the function is called as 

__delay_cycles(1);

 

And assuming this works, would I go the same about creating a 1-second delay? Could I just add "1,000,000" to the function?

 

Thanks for the help.

I wish I had an oscilloscope or a logic analyzer to look at the signals.

[chicken 630]

I wouldn't use _delay_cycles do build a clock or implement time sensitive communication protocols.

 

But with 1MHz clock, _delay_cycles(1000) should be close enough to 1ms (and _delay_cycles(1000000) to 1 second) for basic delays, e.g. when blinking LEDs, waiting for some peripheral to do its thing etc.

 

Note, that if there are other things going on, e.g. interrupt routines, _delay_cycles() might take longer than expected. If you need more precise timing, you will have to setup a timer interrupt and implement delay() similar to what Energia does.

 

PS: @1MHz _delay_cycles(1) will wait 1 us (microsecond), not ms (millisecond).