使用mbed开发st公司提供的开发板很方便，但是在头文件里没有找到如何设置系统的时钟频率的头文件，该怎么设置呢?

还有如何设置AD的采样速率？头文件里好像都没有说

1. /* mbed Microcontroller Library
   
2. * Copyright (c) 2006-2013 ARM Limited
   
3. *
   
4. * Licensed under the Apache License, Version 2.0 (the "License");
   
5. * you may not use this file except in compliance with the License.
   
6. * You may obtain a copy of the License at
   
7. *
   
8. *     http://www.apache.org/licenses/LICENSE-2.0
   
9. *
   
10. * Unless required by applicable law or agreed to in writing, software
    
11. * distributed under the License is distributed on an "AS IS" BASIS,
    
12. * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    
13. * See the License for the specific language governing permissions and
    
14. * limitations under the License.
    
15. */
    
16. #ifndef MBED_ANALOGIN_H
    
17. #define MBED_ANALOGIN_H
    
18. 
    
19. #include "platform.h"
    
20. 
    
21. #if DEVICE_ANALOGIN
    
22. 
    
23. #include "analogin_api.h"
    
24. 
    
25. namespace mbed {
    
26. 
    
27. /** An analog input, used for reading the voltage on a pin
    
28. *
    
29. * Example:
    
30. * @code
    
31. * // Print messages when the AnalogIn is greater than 50%
    
32. *
    
33. * #include "mbed.h"
    
34. *
    
35. * AnalogIn temperature(p20);
    
36. *
    
37. * int main() {
    
38. *     while(1) {
    
39. *         if(temperature > 0.5) {
    
40. *             printf("Too hot! (%f)", temperature.read());
    
41. *         }
    
42. *     }
    
43. * }
    
44. * @endcode
    
45. */
    
46. class AnalogIn {
    
47. 
    
48. public:
    
49. 
    
50.     /** Create an AnalogIn, connected to the specified pin
    
51.      *
    
52.      * @param pin AnalogIn pin to connect to
    
53.      * @param name (optional) A string to identify the object
    
54.      */
    
55.     AnalogIn(PinName pin) {
    
56.         analogin_init(&_adc, pin);
    
57.     }
    
58. 
    
59.     /** Read the input voltage, represented as a float in the range [0.0, 1.0]
    
60.      *
    
61.      * @returns A floating-point value representing the current input voltage, measured as a percentage
    
62.      */
    
63.     float read() {
    
64.         return analogin_read(&_adc);
    
65.     }
    
66. 
    
67.     /** Read the input voltage, represented as an unsigned short in the range [0x0, 0xFFFF]
    
68.      *
    
69.      * @returns
    
70.      *   16-bit unsigned short representing the current input voltage, normalised to a 16-bit value
    
71.      */
    
72.     unsigned short read_u16() {
    
73.         return analogin_read_u16(&_adc);
    
74.     }
    
75. 
    
76. #ifdef MBED_OPERATORS
    
77.     /** An operator shorthand for read()
    
78.      *
    
79.      * The float() operator can be used as a shorthand for read() to simplify common code sequences
    
80.      *
    
81.      * Example:
    
82.      * @code
    
83.      * float x = volume.read();
    
84.      * float x = volume;
    
85.      *
    
86.      * if(volume.read() > 0.25) { ... }
    
87.      * if(volume > 0.25) { ... }
    
88.      * @endcode
    
89.      */
    
90.     operator float() {
    
91.         return read();
    
92.     }
    
93. #endif
    
94. 
    
95. protected:
    
96.     analogin_t _adc;
    
97. };
    
98. 
    
99. } // namespace mbed
    
100. 
     
101. #endif
     
102. 
     
103. #endif
     

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在线版的mbed编译器上无法更改 时钟频率等一些列的东西，建议使用离线版中更改 底层文件实现！

晓枫VS枯叶 发表于 2014-11-27 20:26
在线版的mbed编译器上无法更改 时钟频率等一些列的东西，建议使用离线版中更改 底层文件实现！ ...

离线版指的是keil？

现在keil和IAR上都可以编译了，建议使用IAR，编译速度比mdk快一些！