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|
GAS LISTING /tmp/ccWx46oe.s page 1
1 .file "test.c"
2 __SP_H__ = 0x3e
3 __SP_L__ = 0x3d
4 __SREG__ = 0x3f
5 __tmp_reg__ = 0
6 __zero_reg__ = 1
9 .text
10 .Ltext0:
104 .global delay_ms
106 delay_ms:
107 .stabd 46,0,0
1:test.c **** #include <avr/io.h>
2:test.c **** #include <avr/interrupt.h>
3:test.c **** #include <avr/sleep.h>
4:test.c **** #include <util/delay.h>
5:test.c ****
6:test.c **** void delay_ms(uint32_t time) {
109 .LM0:
110 .LFBB1:
111 0000 0F93 push r16
112 0002 1F93 push r17
113 /* prologue: function */
114 /* frame size = 0 */
115 /* stack size = 2 */
116 .L__stack_usage = 2
7:test.c **** uint32_t i;
8:test.c **** for (i = 0; i < time; i++) {
118 .LM1:
119 0004 00E0 ldi r16,0
120 0006 10E0 ldi r17,0
121 0008 9801 movw r18,r16
122 .L2:
124 .LM2:
125 000a 0617 cp r16,r22
126 000c 1707 cpc r17,r23
127 000e 2807 cpc r18,r24
128 0010 3907 cpc r19,r25
129 0012 01F0 breq .L5
130 .LBB6:
131 .LBB7:
133 .Ltext1:
1:/usr/lib/avr/include/util/delay.h **** /* Copyright (c) 2002, Marek Michalkiewicz
2:/usr/lib/avr/include/util/delay.h **** Copyright (c) 2004,2005,2007 Joerg Wunsch
3:/usr/lib/avr/include/util/delay.h **** Copyright (c) 2007 Florin-Viorel Petrov
4:/usr/lib/avr/include/util/delay.h **** All rights reserved.
5:/usr/lib/avr/include/util/delay.h ****
6:/usr/lib/avr/include/util/delay.h **** Redistribution and use in source and binary forms, with or without
7:/usr/lib/avr/include/util/delay.h **** modification, are permitted provided that the following conditions are met:
8:/usr/lib/avr/include/util/delay.h ****
9:/usr/lib/avr/include/util/delay.h **** * Redistributions of source code must retain the above copyright
10:/usr/lib/avr/include/util/delay.h **** notice, this list of conditions and the following disclaimer.
11:/usr/lib/avr/include/util/delay.h ****
12:/usr/lib/avr/include/util/delay.h **** * Redistributions in binary form must reproduce the above copyright
13:/usr/lib/avr/include/util/delay.h **** notice, this list of conditions and the following disclaimer in
14:/usr/lib/avr/include/util/delay.h **** the documentation and/or other materials provided with the
15:/usr/lib/avr/include/util/delay.h **** distribution.
16:/usr/lib/avr/include/util/delay.h ****
GAS LISTING /tmp/ccWx46oe.s page 2
17:/usr/lib/avr/include/util/delay.h **** * Neither the name of the copyright holders nor the names of
18:/usr/lib/avr/include/util/delay.h **** contributors may be used to endorse or promote products derived
19:/usr/lib/avr/include/util/delay.h **** from this software without specific prior written permission.
20:/usr/lib/avr/include/util/delay.h ****
21:/usr/lib/avr/include/util/delay.h **** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
22:/usr/lib/avr/include/util/delay.h **** AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23:/usr/lib/avr/include/util/delay.h **** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24:/usr/lib/avr/include/util/delay.h **** ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
25:/usr/lib/avr/include/util/delay.h **** LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26:/usr/lib/avr/include/util/delay.h **** CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27:/usr/lib/avr/include/util/delay.h **** SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28:/usr/lib/avr/include/util/delay.h **** INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29:/usr/lib/avr/include/util/delay.h **** CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30:/usr/lib/avr/include/util/delay.h **** ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31:/usr/lib/avr/include/util/delay.h **** POSSIBILITY OF SUCH DAMAGE. */
32:/usr/lib/avr/include/util/delay.h ****
33:/usr/lib/avr/include/util/delay.h **** /* $Id$ */
34:/usr/lib/avr/include/util/delay.h ****
35:/usr/lib/avr/include/util/delay.h **** #ifndef _UTIL_DELAY_H_
36:/usr/lib/avr/include/util/delay.h **** #define _UTIL_DELAY_H_ 1
37:/usr/lib/avr/include/util/delay.h ****
38:/usr/lib/avr/include/util/delay.h **** #ifndef __HAS_DELAY_CYCLES
39:/usr/lib/avr/include/util/delay.h **** #define __HAS_DELAY_CYCLES 1
40:/usr/lib/avr/include/util/delay.h **** #endif
41:/usr/lib/avr/include/util/delay.h ****
42:/usr/lib/avr/include/util/delay.h **** #include <inttypes.h>
43:/usr/lib/avr/include/util/delay.h **** #include <util/delay_basic.h>
44:/usr/lib/avr/include/util/delay.h **** #include <math.h>
45:/usr/lib/avr/include/util/delay.h ****
46:/usr/lib/avr/include/util/delay.h **** /** \file */
47:/usr/lib/avr/include/util/delay.h **** /** \defgroup util_delay <util/delay.h>: Convenience functions for busy-wait delay loops
48:/usr/lib/avr/include/util/delay.h **** \code
49:/usr/lib/avr/include/util/delay.h **** #define F_CPU 1000000UL // 1 MHz
50:/usr/lib/avr/include/util/delay.h **** //#define F_CPU 14.7456E6
51:/usr/lib/avr/include/util/delay.h **** #include <util/delay.h>
52:/usr/lib/avr/include/util/delay.h **** \endcode
53:/usr/lib/avr/include/util/delay.h ****
54:/usr/lib/avr/include/util/delay.h **** \note As an alternative method, it is possible to pass the
55:/usr/lib/avr/include/util/delay.h **** F_CPU macro down to the compiler from the Makefile.
56:/usr/lib/avr/include/util/delay.h **** Obviously, in that case, no \c \#define statement should be
57:/usr/lib/avr/include/util/delay.h **** used.
58:/usr/lib/avr/include/util/delay.h ****
59:/usr/lib/avr/include/util/delay.h **** The functions in this header file are wrappers around the basic
60:/usr/lib/avr/include/util/delay.h **** busy-wait functions from <util/delay_basic.h>. They are meant as
61:/usr/lib/avr/include/util/delay.h **** convenience functions where actual time values can be specified
62:/usr/lib/avr/include/util/delay.h **** rather than a number of cycles to wait for. The idea behind is
63:/usr/lib/avr/include/util/delay.h **** that compile-time constant expressions will be eliminated by
64:/usr/lib/avr/include/util/delay.h **** compiler optimization so floating-point expressions can be used
65:/usr/lib/avr/include/util/delay.h **** to calculate the number of delay cycles needed based on the CPU
66:/usr/lib/avr/include/util/delay.h **** frequency passed by the macro F_CPU.
67:/usr/lib/avr/include/util/delay.h ****
68:/usr/lib/avr/include/util/delay.h **** \note In order for these functions to work as intended, compiler
69:/usr/lib/avr/include/util/delay.h **** optimizations <em>must</em> be enabled, and the delay time
70:/usr/lib/avr/include/util/delay.h **** <em>must</em> be an expression that is a known constant at
71:/usr/lib/avr/include/util/delay.h **** compile-time. If these requirements are not met, the resulting
72:/usr/lib/avr/include/util/delay.h **** delay will be much longer (and basically unpredictable), and
73:/usr/lib/avr/include/util/delay.h **** applications that otherwise do not use floating-point calculations
GAS LISTING /tmp/ccWx46oe.s page 3
74:/usr/lib/avr/include/util/delay.h **** will experience severe code bloat by the floating-point library
75:/usr/lib/avr/include/util/delay.h **** routines linked into the application.
76:/usr/lib/avr/include/util/delay.h ****
77:/usr/lib/avr/include/util/delay.h **** The functions available allow the specification of microsecond, and
78:/usr/lib/avr/include/util/delay.h **** millisecond delays directly, using the application-supplied macro
79:/usr/lib/avr/include/util/delay.h **** F_CPU as the CPU clock frequency (in Hertz).
80:/usr/lib/avr/include/util/delay.h ****
81:/usr/lib/avr/include/util/delay.h **** */
82:/usr/lib/avr/include/util/delay.h ****
83:/usr/lib/avr/include/util/delay.h **** #if !defined(__DOXYGEN__)
84:/usr/lib/avr/include/util/delay.h **** static inline void _delay_us(double __us) __attribute__((always_inline));
85:/usr/lib/avr/include/util/delay.h **** static inline void _delay_ms(double __ms) __attribute__((always_inline));
86:/usr/lib/avr/include/util/delay.h **** #endif
87:/usr/lib/avr/include/util/delay.h ****
88:/usr/lib/avr/include/util/delay.h **** #ifndef F_CPU
89:/usr/lib/avr/include/util/delay.h **** /* prevent compiler error by supplying a default */
90:/usr/lib/avr/include/util/delay.h **** # warning "F_CPU not defined for <util/delay.h>"
91:/usr/lib/avr/include/util/delay.h **** # define F_CPU 1000000UL
92:/usr/lib/avr/include/util/delay.h **** #endif
93:/usr/lib/avr/include/util/delay.h ****
94:/usr/lib/avr/include/util/delay.h **** #ifndef __OPTIMIZE__
95:/usr/lib/avr/include/util/delay.h **** # warning "Compiler optimizations disabled; functions from <util/delay.h> won't work as designed"
96:/usr/lib/avr/include/util/delay.h **** #endif
97:/usr/lib/avr/include/util/delay.h ****
98:/usr/lib/avr/include/util/delay.h **** #if __HAS_DELAY_CYCLES && defined(__OPTIMIZE__) && \
99:/usr/lib/avr/include/util/delay.h **** !defined(__DELAY_BACKWARD_COMPATIBLE__) && \
100:/usr/lib/avr/include/util/delay.h **** __STDC_HOSTED__
101:/usr/lib/avr/include/util/delay.h **** # include <math.h>
102:/usr/lib/avr/include/util/delay.h **** #endif
103:/usr/lib/avr/include/util/delay.h ****
104:/usr/lib/avr/include/util/delay.h **** /**
105:/usr/lib/avr/include/util/delay.h **** \ingroup util_delay
106:/usr/lib/avr/include/util/delay.h ****
107:/usr/lib/avr/include/util/delay.h **** Perform a delay of \c __ms milliseconds, using _delay_loop_2().
108:/usr/lib/avr/include/util/delay.h ****
109:/usr/lib/avr/include/util/delay.h **** The macro F_CPU is supposed to be defined to a
110:/usr/lib/avr/include/util/delay.h **** constant defining the CPU clock frequency (in Hertz).
111:/usr/lib/avr/include/util/delay.h ****
112:/usr/lib/avr/include/util/delay.h **** The maximal possible delay is 262.14 ms / F_CPU in MHz.
113:/usr/lib/avr/include/util/delay.h ****
114:/usr/lib/avr/include/util/delay.h **** When the user request delay which exceed the maximum possible one,
115:/usr/lib/avr/include/util/delay.h **** _delay_ms() provides a decreased resolution functionality. In this
116:/usr/lib/avr/include/util/delay.h **** mode _delay_ms() will work with a resolution of 1/10 ms, providing
117:/usr/lib/avr/include/util/delay.h **** delays up to 6.5535 seconds (independent from CPU frequency). The
118:/usr/lib/avr/include/util/delay.h **** user will not be informed about decreased resolution.
119:/usr/lib/avr/include/util/delay.h ****
120:/usr/lib/avr/include/util/delay.h **** If the avr-gcc toolchain has __builtin_avr_delay_cycles(unsigned long)
121:/usr/lib/avr/include/util/delay.h **** support, maximal possible delay is 4294967.295 ms/ F_CPU in MHz. For
122:/usr/lib/avr/include/util/delay.h **** values greater than the maximal possible delay, overflows results in
123:/usr/lib/avr/include/util/delay.h **** no delay i.e., 0ms.
124:/usr/lib/avr/include/util/delay.h ****
125:/usr/lib/avr/include/util/delay.h **** Conversion of __us into clock cycles may not always result in integer.
126:/usr/lib/avr/include/util/delay.h **** By default, the clock cycles rounded up to next integer. This ensures that
127:/usr/lib/avr/include/util/delay.h **** the user gets atleast __us microseconds of delay.
128:/usr/lib/avr/include/util/delay.h ****
129:/usr/lib/avr/include/util/delay.h **** Alternatively, user can define __DELAY_ROUND_DOWN__ and __DELAY_ROUND_CLOSEST__
130:/usr/lib/avr/include/util/delay.h **** to round down and round to closest integer.
GAS LISTING /tmp/ccWx46oe.s page 4
131:/usr/lib/avr/include/util/delay.h ****
132:/usr/lib/avr/include/util/delay.h **** Note: The new implementation of _delay_ms(double __ms) with
133:/usr/lib/avr/include/util/delay.h **** __builtin_avr_delay_cycles(unsigned long) support is not backward compatible.
134:/usr/lib/avr/include/util/delay.h **** User can define __DELAY_BACKWARD_COMPATIBLE__ to get a backward compatible delay.
135:/usr/lib/avr/include/util/delay.h **** Also, the backward compatible
136:/usr/lib/avr/include/util/delay.h **** algorithm will be chosen if the code is compiled in a <em>freestanding
137:/usr/lib/avr/include/util/delay.h **** environment</em> (GCC option \c -ffreestanding), as the math functions
138:/usr/lib/avr/include/util/delay.h **** required for rounding are not available to the compiler then.
139:/usr/lib/avr/include/util/delay.h ****
140:/usr/lib/avr/include/util/delay.h **** */
141:/usr/lib/avr/include/util/delay.h **** void
142:/usr/lib/avr/include/util/delay.h **** _delay_ms(double __ms)
143:/usr/lib/avr/include/util/delay.h **** {
144:/usr/lib/avr/include/util/delay.h **** double __tmp ;
145:/usr/lib/avr/include/util/delay.h **** #if __HAS_DELAY_CYCLES && defined(__OPTIMIZE__) && \
146:/usr/lib/avr/include/util/delay.h **** !defined(__DELAY_BACKWARD_COMPATIBLE__) && \
147:/usr/lib/avr/include/util/delay.h **** __STDC_HOSTED__
148:/usr/lib/avr/include/util/delay.h **** uint32_t __ticks_dc;
149:/usr/lib/avr/include/util/delay.h **** extern void __builtin_avr_delay_cycles(unsigned long);
150:/usr/lib/avr/include/util/delay.h **** __tmp = ((F_CPU) / 1e3) * __ms;
151:/usr/lib/avr/include/util/delay.h ****
152:/usr/lib/avr/include/util/delay.h **** #if defined(__DELAY_ROUND_DOWN__)
153:/usr/lib/avr/include/util/delay.h **** __ticks_dc = (uint32_t)fabs(__tmp);
154:/usr/lib/avr/include/util/delay.h ****
155:/usr/lib/avr/include/util/delay.h **** #elif defined(__DELAY_ROUND_CLOSEST__)
156:/usr/lib/avr/include/util/delay.h **** __ticks_dc = (uint32_t)(fabs(__tmp)+0.5);
157:/usr/lib/avr/include/util/delay.h ****
158:/usr/lib/avr/include/util/delay.h **** #else
159:/usr/lib/avr/include/util/delay.h **** //round up by default
160:/usr/lib/avr/include/util/delay.h **** __ticks_dc = (uint32_t)(ceil(fabs(__tmp)));
161:/usr/lib/avr/include/util/delay.h **** #endif
162:/usr/lib/avr/include/util/delay.h ****
163:/usr/lib/avr/include/util/delay.h **** __builtin_avr_delay_cycles(__ticks_dc);
135 .LM3:
136 0014 EFEC ldi r30,lo8(1999)
137 0016 F7E0 ldi r31,hi8(1999)
138 0018 3197 1: sbiw r30,1
139 001a 01F4 brne 1b
140 001c 00C0 rjmp .
141 001e 0000 nop
142 .LBE7:
143 .LBE6:
145 .Ltext2:
147 .LM4:
148 0020 0F5F subi r16,-1
149 0022 1F4F sbci r17,-1
150 0024 2F4F sbci r18,-1
151 0026 3F4F sbci r19,-1
152 0028 00C0 rjmp .L2
153 .L5:
154 /* epilogue start */
9:test.c **** _delay_ms(1);
10:test.c **** }
11:test.c **** }
156 .LM5:
157 002a 1F91 pop r17
158 002c 0F91 pop r16
GAS LISTING /tmp/ccWx46oe.s page 5
159 002e 0895 ret
164 .Lscope1:
166 .stabd 78,0,0
167 .section .text.startup,"ax",@progbits
169 .global main
171 main:
172 .stabd 46,0,0
12:test.c ****
13:test.c **** #define NOOP asm volatile("nop" ::)
14:test.c ****
15:test.c ****
16:test.c **** static void setup_clock( void )
17:test.c **** {
18:test.c **** /*Examine Page 33*/
19:test.c ****
20:test.c **** CLKPR = 0x80; /*Setup CLKPCE to be receptive*/
21:test.c **** CLKPR = 0x00; /*No scalar*/
22:test.c **** OSCCAL = 0x80; //B8 is bottom E8 is top.
23:test.c **** }
24:test.c ****
25:test.c **** int main( )
26:test.c **** {
174 .LM6:
175 .LFBB2:
176 /* prologue: function */
177 /* frame size = 0 */
178 /* stack size = 0 */
179 .L__stack_usage = 0
27:test.c **** cli();
181 .LM7:
182 /* #APP */
183 ; 27 "test.c" 1
184 0000 F894 cli
185 ; 0 "" 2
186 /* #NOAPP */
187 .LBB12:
188 .LBB13:
20:test.c **** CLKPR = 0x00; /*No scalar*/
190 .LM8:
191 0002 80E8 ldi r24,lo8(-128)
192 0004 86BD out 0x26,r24
21:test.c **** OSCCAL = 0x80; //B8 is bottom E8 is top.
194 .LM9:
195 0006 16BC out 0x26,__zero_reg__
22:test.c **** }
197 .LM10:
198 0008 81BF out 0x31,r24
199 .LBE13:
200 .LBE12:
28:test.c **** setup_clock();
29:test.c **** DDRB = _BV(4);
202 .LM11:
203 000a 80E1 ldi r24,lo8(16)
204 000c 87BB out 0x17,r24
30:test.c **** uint8_t marker;
31:test.c ****
32:test.c **** while(1)
GAS LISTING /tmp/ccWx46oe.s page 6
33:test.c **** {
34:test.c **** marker = 0x05;
35:test.c **** do{
36:test.c **** PORTB = _BV(4);
206 .LM12:
207 000e 90E1 ldi r25,lo8(16)
208 .L8:
26:test.c **** cli();
210 .LM13:
211 0010 85E0 ldi r24,lo8(5)
212 .L7:
214 .LM14:
215 0012 98BB out 0x18,r25
37:test.c **** marker--;
38:test.c **** PORTB = 0;
217 .LM15:
218 0014 18BA out 0x18,__zero_reg__
219 0016 8150 subi r24,lo8(-(-1))
39:test.c **** } while( marker );
221 .LM16:
222 0018 01F4 brne .L7
223 .LBB14:
224 .LBB15:
226 .Ltext3:
164:/usr/lib/avr/include/util/delay.h ****
165:/usr/lib/avr/include/util/delay.h **** #else
166:/usr/lib/avr/include/util/delay.h **** uint16_t __ticks;
167:/usr/lib/avr/include/util/delay.h **** __tmp = ((F_CPU) / 4e3) * __ms;
168:/usr/lib/avr/include/util/delay.h **** if (__tmp < 1.0)
169:/usr/lib/avr/include/util/delay.h **** __ticks = 1;
170:/usr/lib/avr/include/util/delay.h **** else if (__tmp > 65535)
171:/usr/lib/avr/include/util/delay.h **** {
172:/usr/lib/avr/include/util/delay.h **** // __ticks = requested delay in 1/10 ms
173:/usr/lib/avr/include/util/delay.h **** __ticks = (uint16_t) (__ms * 10.0);
174:/usr/lib/avr/include/util/delay.h **** while(__ticks)
175:/usr/lib/avr/include/util/delay.h **** {
176:/usr/lib/avr/include/util/delay.h **** // wait 1/10 ms
177:/usr/lib/avr/include/util/delay.h **** _delay_loop_2(((F_CPU) / 4e3) / 10);
178:/usr/lib/avr/include/util/delay.h **** __ticks --;
179:/usr/lib/avr/include/util/delay.h **** }
180:/usr/lib/avr/include/util/delay.h **** return;
181:/usr/lib/avr/include/util/delay.h **** }
182:/usr/lib/avr/include/util/delay.h **** else
183:/usr/lib/avr/include/util/delay.h **** __ticks = (uint16_t)__tmp;
184:/usr/lib/avr/include/util/delay.h **** _delay_loop_2(__ticks);
185:/usr/lib/avr/include/util/delay.h **** #endif
186:/usr/lib/avr/include/util/delay.h **** }
187:/usr/lib/avr/include/util/delay.h ****
188:/usr/lib/avr/include/util/delay.h **** /**
189:/usr/lib/avr/include/util/delay.h **** \ingroup util_delay
190:/usr/lib/avr/include/util/delay.h ****
191:/usr/lib/avr/include/util/delay.h **** Perform a delay of \c __us microseconds, using _delay_loop_1().
192:/usr/lib/avr/include/util/delay.h ****
193:/usr/lib/avr/include/util/delay.h **** The macro F_CPU is supposed to be defined to a
194:/usr/lib/avr/include/util/delay.h **** constant defining the CPU clock frequency (in Hertz).
195:/usr/lib/avr/include/util/delay.h ****
196:/usr/lib/avr/include/util/delay.h **** The maximal possible delay is 768 us / F_CPU in MHz.
GAS LISTING /tmp/ccWx46oe.s page 7
197:/usr/lib/avr/include/util/delay.h ****
198:/usr/lib/avr/include/util/delay.h **** If the user requests a delay greater than the maximal possible one,
199:/usr/lib/avr/include/util/delay.h **** _delay_us() will automatically call _delay_ms() instead. The user
200:/usr/lib/avr/include/util/delay.h **** will not be informed about this case.
201:/usr/lib/avr/include/util/delay.h ****
202:/usr/lib/avr/include/util/delay.h **** If the avr-gcc toolchain has __builtin_avr_delay_cycles(unsigned long)
203:/usr/lib/avr/include/util/delay.h **** support, maximal possible delay is 4294967.295 us/ F_CPU in MHz. For
204:/usr/lib/avr/include/util/delay.h **** values greater than the maximal possible delay, overflow results in
205:/usr/lib/avr/include/util/delay.h **** no delay i.e., 0us.
206:/usr/lib/avr/include/util/delay.h ****
207:/usr/lib/avr/include/util/delay.h **** Conversion of __us into clock cycles may not always result in integer.
208:/usr/lib/avr/include/util/delay.h **** By default, the clock cycles rounded up to next integer. This ensures that
209:/usr/lib/avr/include/util/delay.h **** the user gets atleast __us microseconds of delay.
210:/usr/lib/avr/include/util/delay.h ****
211:/usr/lib/avr/include/util/delay.h **** Alternatively, user can define __DELAY_ROUND_DOWN__ and __DELAY_ROUND_CLOSEST__
212:/usr/lib/avr/include/util/delay.h **** to round down and round to closest integer.
213:/usr/lib/avr/include/util/delay.h ****
214:/usr/lib/avr/include/util/delay.h **** Note: The new implementation of _delay_us(double __us) with
215:/usr/lib/avr/include/util/delay.h **** __builtin_avr_delay_cycles(unsigned long) support is not backward compatible.
216:/usr/lib/avr/include/util/delay.h **** User can define __DELAY_BACKWARD_COMPATIBLE__ to get a backward compatible delay.
217:/usr/lib/avr/include/util/delay.h **** Also, the backward compatible
218:/usr/lib/avr/include/util/delay.h **** algorithm will be chosen if the code is compiled in a <em>freestanding
219:/usr/lib/avr/include/util/delay.h **** environment</em> (GCC option \c -ffreestanding), as the math functions
220:/usr/lib/avr/include/util/delay.h **** required for rounding are not available to the compiler then.
221:/usr/lib/avr/include/util/delay.h ****
222:/usr/lib/avr/include/util/delay.h **** */
223:/usr/lib/avr/include/util/delay.h **** void
224:/usr/lib/avr/include/util/delay.h **** _delay_us(double __us)
225:/usr/lib/avr/include/util/delay.h **** {
226:/usr/lib/avr/include/util/delay.h **** double __tmp ;
227:/usr/lib/avr/include/util/delay.h **** #if __HAS_DELAY_CYCLES && defined(__OPTIMIZE__) && \
228:/usr/lib/avr/include/util/delay.h **** !defined(__DELAY_BACKWARD_COMPATIBLE__) && \
229:/usr/lib/avr/include/util/delay.h **** __STDC_HOSTED__
230:/usr/lib/avr/include/util/delay.h **** uint32_t __ticks_dc;
231:/usr/lib/avr/include/util/delay.h **** extern void __builtin_avr_delay_cycles(unsigned long);
232:/usr/lib/avr/include/util/delay.h **** __tmp = ((F_CPU) / 1e6) * __us;
233:/usr/lib/avr/include/util/delay.h ****
234:/usr/lib/avr/include/util/delay.h **** #if defined(__DELAY_ROUND_DOWN__)
235:/usr/lib/avr/include/util/delay.h **** __ticks_dc = (uint32_t)fabs(__tmp);
236:/usr/lib/avr/include/util/delay.h ****
237:/usr/lib/avr/include/util/delay.h **** #elif defined(__DELAY_ROUND_CLOSEST__)
238:/usr/lib/avr/include/util/delay.h **** __ticks_dc = (uint32_t)(fabs(__tmp)+0.5);
239:/usr/lib/avr/include/util/delay.h ****
240:/usr/lib/avr/include/util/delay.h **** #else
241:/usr/lib/avr/include/util/delay.h **** //round up by default
242:/usr/lib/avr/include/util/delay.h **** __ticks_dc = (uint32_t)(ceil(fabs(__tmp)));
243:/usr/lib/avr/include/util/delay.h **** #endif
244:/usr/lib/avr/include/util/delay.h ****
245:/usr/lib/avr/include/util/delay.h **** __builtin_avr_delay_cycles(__ticks_dc);
228 .LM17:
229 001a E3E3 ldi r30,lo8(-32205)
230 001c F2E8 ldi r31,hi8(-32205)
231 001e 3197 1: sbiw r30,1
232 0020 01F4 brne 1b
233 0022 00C0 rjmp .
234 0024 0000 nop
235 0026 00C0 rjmp .L8
GAS LISTING /tmp/ccWx46oe.s page 8
236 .LBE15:
237 .LBE14:
239 .Lscope2:
241 .stabd 78,0,0
242 .text
244 .Letext0:
245 .ident "GCC: (GNU) 4.9.2"
GAS LISTING /tmp/ccWx46oe.s page 9
DEFINED SYMBOLS
*ABS*:0000000000000000 test.c
/tmp/ccWx46oe.s:2 *ABS*:000000000000003e __SP_H__
/tmp/ccWx46oe.s:3 *ABS*:000000000000003d __SP_L__
/tmp/ccWx46oe.s:4 *ABS*:000000000000003f __SREG__
/tmp/ccWx46oe.s:5 *ABS*:0000000000000000 __tmp_reg__
/tmp/ccWx46oe.s:6 *ABS*:0000000000000001 __zero_reg__
/tmp/ccWx46oe.s:106 .text:0000000000000000 delay_ms
/tmp/ccWx46oe.s:171 .text.startup:0000000000000000 main
NO UNDEFINED SYMBOLS
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