FlexProp P1 Clock Frequency "C"

Shawna · 2020-11-14 02:11

How does one change the Clock Mode and Frequency for the P1 in FlexPropC.

The FlexProp help file says...

P1 Clock Frequency

In C code, the P1 clock frequency defaults to 80 MHz, assuming a 5 MHz crystal and xtal1 + pll16x clock mode. This is a common configuration. You may override it with the builtin clkset function, which works the same as the Spin clkset builtin.

Its been awhile since I have messed with spin but the propeller manual says....

clkset(%01101100, 4_000_000)           'Set to XTAL1 + PLL2x

I have tried multiple pieces of code but can't get anything to compile.

Shawna · 2020-11-14 02:18

I think I found it.

#define clkset(a, b) _clkset(a, b)

Seems it has to be placed after int main.

int main(){  
clkset(a, b)
}

I was trying to set it before.

Shawna · 2020-11-14 02:26

Something like this.

#include <simpletools.h>

int counts = 0;
int Mode = 111;		//XTAL1 + PLL16X
int MHZ = 80000000;

int main(){
    clkset(Mode , MHZ);                      // Set system mode and clock.     
    while(1){
	print("%c" , 16);			// Clear PST    
	print("Count = %d\n", counts);
        pause(100);  
        counts = counts + 1;
    }
}

yeti · 2020-11-14 10:03

—▷ https://github.com/totalspectrum/spin2cpp/blob/master/doc/c.md#runtime-environment

So you only need to set it if you don't want the default.
This even applies to FlexSpin.

Shawna · 2020-11-14 14:42

yeti wrote: »

So you only need to set it if you don't want the default.
This even applies to FlexSpin.

Yeah, that's a good point.

I know this but I am trying to overclock the prop and was having problems using the clkset(mode, frequency) function. I figured once I was able to get the code to compile I would be good but I am still having issues. I am hesitant to ask overclocking questions in this thread because I started a similar one 9 months ago for simpletools.

FlexProp P1 Clock Frequency "C"

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