circuitpython/atmel-samd/asf/common2/services/delay/sam0/cycle_counter.c
Scott Shawcroft 8f26d181c3 Blinking the LED works. Clocks should be set up correctly.
Everything works fine without USB being plugged in but faults (I think) when USB is plugged in. This is switched away from the USB code from the bootloader onto the USB code thats generated by Atmel Studio using the high level classes from ASF.
2016-08-22 23:53:11 -07:00

77 lines
2.3 KiB
C

/**
* \file
*
* \brief ARM functions for busy-wait delay loops
*
* Copyright (c) 2012-2015 Atmel Corporation. All rights reserved.
*
* \asf_license_start
*
* \page License
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. The name of Atmel may not be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* 4. This software may only be redistributed and used in connection with an
* Atmel microcontroller product.
*
* THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
* EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* \asf_license_stop
*
*/
/*
* Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a>
*/
#include "cycle_counter.h"
#include "delay.h"
/**
* \brief Initialize the delay driver.
*
* Not used in cycle mode.
*/
void delay_init(void)
{
}
// Delay loop is put to SRAM so that FWS will not affect delay time
OPTIMIZE_HIGH
RAMFUNC
void portable_delay_cycles(unsigned long n)
{
UNUSED(n);
__asm (
"loop: DMB \n"
#ifdef __ICCARM__
"SUBS r0, r0, #1 \n"
#else
"SUB r0, r0, #1 \n"
#endif
"CMP r0, #0 \n"
"BNE loop "
);
}