crashtest-r0ket/basic/delayms.c

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#include <sysdefs.h>
#include "lpc134x.h"
/**************************************************************************/
/*!
Approximates a 1 millisecond delay using "nop". This is less
accurate than a dedicated timer, but is useful in certain situations.
The number of ticks to delay depends on the optimisation level set
when compiling (-O). Depending on the compiler settings, one of the
two defined values for 'delay' should be used.
*/
/**************************************************************************/
void delayms(uint32_t ms)
{
uint32_t delay = ms * ((CFG_CPU_CCLK / 100) / 45); // Release Mode (-Os)
// uint32_t delay = ms * ((CFG_CPU_CCLK / 100) / 120); // Debug Mode (No optimisations)
while (delay > 0)
{
__asm volatile ("nop");
delay--;
}
}