mirror of
https://github.com/greatscottgadgets/hackrf.git
synced 2026-02-27 20:15:44 +01:00
55 lines
1.6 KiB
C
55 lines
1.6 KiB
C
/*
|
|
* Copyright 2026 Great Scott Gadgets <info@greatscottgadgets.com>
|
|
*
|
|
* This file is part of HackRF.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2, or (at your option)
|
|
* any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; see the file COPYING. If not, write to
|
|
* the Free Software Foundation, Inc., 51 Franklin Street,
|
|
* Boston, MA 02110-1301, USA.
|
|
*/
|
|
|
|
#include "delay.h"
|
|
|
|
void delay(uint32_t duration)
|
|
{
|
|
uint32_t i;
|
|
|
|
for (i = 0; i < duration; i++) {
|
|
__asm__("nop");
|
|
}
|
|
}
|
|
|
|
void delay_us_at_mhz(uint32_t us, uint32_t mhz)
|
|
{
|
|
#if defined(LPC43XX_M4)
|
|
// The loop below takes 3 cycles per iteration.
|
|
uint32_t loop_iterations = (us * mhz) / 3;
|
|
asm volatile("start%=:\n"
|
|
" subs %[ITERATIONS], #1\n" // 1 cycle
|
|
" bpl start%=\n" // 2 cycles
|
|
:
|
|
: [ITERATIONS] "r"(loop_iterations));
|
|
#elif defined(LPC43XX_M0)
|
|
// The loop below takes 4 cycles per iteration.
|
|
uint32_t loop_iterations = (us * mhz) / 4;
|
|
asm volatile("start%=:\n"
|
|
" sub %[ITERATIONS], #1\n" // 1 cycle
|
|
" bpl start%=\n" // 3 cycles
|
|
:
|
|
: [ITERATIONS] "r"(loop_iterations));
|
|
#else
|
|
#error "No delay loop implementation"
|
|
#endif
|
|
}
|