Micropython教程实例之USB－HID应用（萝卜学科编程）

1.引言

USB－HID是Human Interface Device的缩写，属于人机交互操作的设备，如USB鼠标，USB键盘，USB游戏操纵杆，USB触摸板，USB轨迹球、电话拨号设备、VCR遥控等等设备。 TPYBV101除了具有usb host功能以外，还可作为USB－HID设备来应用，这里重点讲述如果作为鼠标和键盘使用。（萝卜学科编程tpyboard。com）

2.TPYBV101作为鼠标应用

TPYBV101作为鼠标的应用可以参考micropython官方实例中的usb-mouse应用。这里以官方实例为例。

（1）编辑 boot.py 文件以更改 USB—mouse 的确认方式。具体如下：

<span style="font-family: 宋体, SimSun; font-size: 12px;">

# boot.py -- run on boot-up<br>

# can run arbitrary Python, but best to keep it minimal<br>import pyb<br>

#pyb.main('main.py')<br>

# main script to run after this one

#pyb.usb_mode('CDC+MSC')<br>

# act as a serial and a storage device<br>pyb.usb_mode('CDC+HID')<br>

# act as a serial device and a mouse<br></span>

其实就是去掉了pyb.usb_mode('CDC+HID')前的注释符。这里pyb.usb_mode()，

定义了HID的设备，默认为mouse，也可以用

pyb.usb_mode('CDC+HID',hid=pyb.hid_mouse)

如果是键盘，应改为

pyb.usb_mode('CDC+HID',hid=pyb.hid_keyboard)

（2）REPL调试鼠标事件

这里依然用putty进行REPL调试。当进行完（1）再次启动时，会发现原本会出现的u盘没有了，此时设备的串口也可能发生了改变，因此在连接Putty前要先确认一下串口。在putty中，输入:（萝卜学科编程tpyboard。com）

pyb.hid((0,10,0,0))  #注意这里两层括号

回车后，会发现鼠标向右移动了10个像素。pyb.hid()的具体用法：

pyb.hid((buttons, x, y, z))

这里buttons取0,1,2,3分别表示0移动，1按下左键，2按下中键，3按下右键。这句也可以用pyb.USB_HID().send((buttons, x, y, z))，效果是一样的。

（3）鼠标左右摇晃，代码如下：

>>> import math

>>> def osc(n, d):

...   for i in range(n):

...     pyb.hid((0, int(20 * math.sin(i / 10)), 0, 0))

...     pyb.delay(d)

...

>>> osc(100, 50)

这段代码也可以写到main.py中，这时大家可能会问，u盘没了，main.py怎么编辑啊。这里需要进入TPYBV101的安全模式。按住usr键，按一下reset，此时led2与led3交替亮，当led3亮起，led2没亮时，松开usr，此时led3快闪后，可以发现u盘挂载出来了，这时可以修改main.py文件。（萝卜学科编程tpyboard。com）

#main.py

import math

import pyb

def osc(n, d):

for i in range(n):

    pyb.hid((0, int(20 * math.sin(i / 10)), 0, 0))

    pyb.delay(d)

osc(100, 50)

保存后，按reset重启后，就可以看到效果了。

（4）加上加速度传感器的鼠标（官方例程）

用加速度传感器制作一个能根据 TPYBoard 板角度移动而移动的鼠标。相关的代码可以直接在交互式解释器里边完成，或者放入 main.py 文件中。在这里我们选择放入 main.py 文件。（萝卜学科编程tpyboard。com）

在 main.py 中代码：

import pyb

switch = pyb.Switch()

accel = pyb.Accel()

while not switch():

    pyb.hid((0, accel.x(), accel.y(), 0))

    pyb.delay(20）

保存文件，退出或卸载 TPYBoard 设备。通过复位按键重置，其将再次成为鼠标，且根据板的倾斜角度移动鼠标。你应该能注意到 y轴方向是颠倒的。这个问题很容易解决：在上述的 pyb.hid( )行里，y 轴方向前边加上负号即可。（萝卜学科编程tpyboard。com）

3、TPYBV10x作为键盘应用

（1） 编辑 boot.py 文件，定义usb-keyboard

# boot.py -- run on boot-up

# can run arbitrary Python, but best to keep it minimal

  

import machine

import pyb

#pyb.main('main.py') # main script to run after this one

#pyb.usb_mode('CDC+MSC') # act as a serial and a storage device

pyb.usb_mode('CDC+HID',hid=pyb.hid_keyboard) # act as a serial device and a keyboard

（2）按键测试，这里为了便于查看，我们修改main.py文件：

         # main.py -- put your code here!

         hid=pyb.USB_HID()

         def release_key_once():

             buf = bytearray(8) # report is 8 bytes long

             buf[2] = 0

             hid.send(buf) # key released

             pyb.delay(10)

         def press_key_once(key):

             buf = bytearray(8) # report is 8 bytes long

             buf[2] = key

             hid.send(buf) # key released

             pyb.delay(10)

         def press_2key(key1,key2):

             buf = bytearray(8) # report is 8 bytes long

             buf[2] = key1

             buf[3] = key2

             hid.send(buf) # key released

             pyb.delay(10)

         def release_2key():

             buf = bytearray(8) # report is 8 bytes long

             buf[2] = 0

             buf[3] = 0

             hid.send(buf) # key released

             pyb.delay(10)

         pyb.delay(1000)

         press_key_once(0x04)

         release_key_once()

         pyb.delay(1000)

         press_key_once(0x05)

         release_key_once()

         pyb.delay(1000)

         press_key_once(0x2B)

         release_key_once()

         pyb.delay(1000)

         press_key_once(0x28)

         release_key_once()

         pyb.delay(1000)

         press_key_once(0x06)

         release_key_once()

         pyb.delay(1000)

         press_key_once(0x07)

         release_key_once()

         pyb.delay(1000)

         press_2key(0x08,0x09)

         release_2key()

         pyb.delay(1000)

这个程序定义了按下一个键press_key_once(key)，抬起一个键 release_key_once()，按下两个键press_2key(key1,key2)，抬起两个键release_2key()的方法。具体运行效果，可先打开一个记事本，然后按一下reset键，或者插拔一次usb口，最后可以看到在记事本里，先打入ab，接着是tab，回车，接着cdef，除了ef几乎同时出现，前面的输入间都间隔了1秒。（萝卜学科编程tpyboard。com）

（3）按键值的定义

为什么上面的0x04是a，0x05是b呢，这里的定义具体如下：

         #define KEY_NONE                               0x00

         #define KEY_ERRORROLLOVER                      0x01

         #define KEY_POSTFAIL                           0x02

         #define KEY_ERRORUNDEFINED                     0x03

         #define KEY_A                                  0x04

         #define KEY_B                                  0x05

         #define KEY_C                                  0x06

         #define KEY_D                                  0x07

         #define KEY_E                                  0x08

         #define KEY_F                                  0x09

         #define KEY_G                                  0x0A

         #define KEY_H                                  0x0B

         #define KEY_I                                  0x0C

         #define KEY_J                                  0x0D

         #define KEY_K                                  0x0E

         #define KEY_L                                  0x0F

         #define KEY_M                                  0x10

         #define KEY_N                                  0x11

         #define KEY_O                                  0x12

         #define KEY_P                                  0x13

         #define KEY_Q                                  0x14

         #define KEY_R                                  0x15

         #define KEY_S                                  0x16

         #define KEY_T                                  0x17

         #define KEY_U                                  0x18

         #define KEY_V                                  0x19

         #define KEY_W                                  0x1A

         #define KEY_X                                  0x1B

         #define KEY_Y                                  0x1C

         #define KEY_Z                                  0x1D

         #define KEY_1_EXCLAMATION_MARK                 0x1E

         #define KEY_2_AT                               0x1F

         #define KEY_3_NUMBER_SIGN                      0x20

         #define KEY_4_DOLLAR                           0x21

         #define KEY_5_PERCENT                          0x22

         #define KEY_6_CARET                            0x23

         #define KEY_7_AMPERSAND                        0x24

         #define KEY_8_ASTERISK                         0x25

         #define KEY_9_OPARENTHESIS                     0x26

         #define KEY_0_CPARENTHESIS                     0x27

         #define KEY_ENTER                              0x28

         #define KEY_ESCAPE                             0x29

         #define KEY_BACKSPACE                          0x2A

         #define KEY_TAB                                0x2B

         #define KEY_SPACEBAR                           0x2C

         #define KEY_MINUS_UNDERSCORE                   0x2D

         #define KEY_EQUAL_PLUS                         0x2E

         #define KEY_OBRACKET_AND_OBRACE                0x2F

         #define KEY_CBRACKET_AND_CBRACE                0x30

         #define KEY_BACKSLASH_VERTICAL_BAR             0x31

         #define KEY_NONUS_NUMBER_SIGN_TILDE            0x32

         #define KEY_SEMICOLON_COLON                    0x33

         #define KEY_SINGLE_AND_DOUBLE_QUOTE            0x34

         #define KEY_GRAVE ACCENT AND TILDE             0x35

         #define KEY_COMMA_AND_LESS                     0x36

         #define KEY_DOT_GREATER                        0x37

         #define KEY_SLASH_QUESTION                     0x38

         #define KEY_CAPS LOCK                          0x39

         #define KEY_F1                                 0x3A

         #define KEY_F2                                 0x3B

         #define KEY_F3                                 0x3C

         #define KEY_F4                                 0x3D

         #define KEY_F5                                 0x3E

         #define KEY_F6                                 0x3F

         #define KEY_F7                                 0x40

         #define KEY_F8                                 0x41

         #define KEY_F9                                 0x42

         #define KEY_F10                                0x43

         #define KEY_F11                                0x44

         #define KEY_F12                                0x45

         #define KEY_PRINTSCREEN                        0x46

         #define KEY_SCROLL LOCK                        0x47

         #define KEY_PAUSE                              0x48

         #define KEY_INSERT                             0x49

         #define KEY_HOME                               0x4A

         #define KEY_PAGEUP                             0x4B

         #define KEY_DELETE                             0x4C

         #define KEY_END1                               0x4D

         #define KEY_PAGEDOWN                           0x4E

         #define KEY_RIGHTARROW                         0x4F

         #define KEY_LEFTARROW                          0x50

         #define KEY_DOWNARROW                          0x51

         #define KEY_UPARROW                            0x52

         #define KEY_KEYPAD_NUM_LOCK_AND_CLEAR          0x53

         #define KEY_KEYPAD_SLASH                       0x54

         #define KEY_KEYPAD_ASTERIKS                    0x55

         #define KEY_KEYPAD_MINUS                       0x56

         #define KEY_KEYPAD_PLUS                        0x57

         #define KEY_KEYPAD_ENTER                       0x58

         #define KEY_KEYPAD_1_END                       0x59

         #define KEY_KEYPAD_2_DOWN_ARROW                0x5A

         #define KEY_KEYPAD_3_PAGEDN                    0x5B

         #define KEY_KEYPAD_4_LEFT_ARROW                0x5C

         #define KEY_KEYPAD_5                           0x5D

         #define KEY_KEYPAD_6_RIGHT_ARROW               0x5E

         #define KEY_KEYPAD_7_HOME                      0x5F

         #define KEY_KEYPAD_8_UP_ARROW                  0x60

         #define KEY_KEYPAD_9_PAGEUP                    0x61

         #define KEY_KEYPAD_0_INSERT                    0x62

         #define KEY_KEYPAD_DECIMAL_SEPARATOR_DELETE    0x63

         #define KEY_NONUS_BACK_SLASH_VERTICAL_BAR      0x64

         #define KEY_APPLICATION                        0x65

         #define KEY_POWER                              0x66

         #define KEY_KEYPAD_EQUAL                       0x67

         #define KEY_F13                                0x68

         #define KEY_F14                                0x69

         #define KEY_F15                                0x6A

         #define KEY_F16                                0x6B

         #define KEY_F17                                0x6C

         #define KEY_F18                                0x6D

         #define KEY_F19                                0x6E

         #define KEY_F20                                0x6F

         #define KEY_F21                                0x70

         #define KEY_F22                                0x71

         #define KEY_F23                                0x72

         #define KEY_F24                                0x73

         #define KEY_EXECUTE                            0x74

         #define KEY_HELP                               0x75

         #define KEY_MENU                               0x76

         #define KEY_SELECT                             0x77

         #define KEY_STOP                               0x78

         #define KEY_AGAIN                              0x79

         #define KEY_UNDO                               0x7A

         #define KEY_CUT                                0x7B

         #define KEY_COPY                               0x7C

         #define KEY_PASTE                              0x7D

         #define KEY_FIND                               0x7E

         #define KEY_MUTE                               0x7F

         #define KEY_VOLUME_UP                          0x80

         #define KEY_VOLUME_DOWN                        0x81

         #define KEY_LOCKING_CAPS_LOCK                  0x82

         #define KEY_LOCKING_NUM_LOCK                   0x83

         #define KEY_LOCKING_SCROLL_LOCK                0x84

         #define KEY_KEYPAD_COMMA                       0x85

         #define KEY_KEYPAD_EQUAL_SIGN                  0x86

         #define KEY_INTERNATIONAL1                     0x87

         #define KEY_INTERNATIONAL2                     0x88

         #define KEY_INTERNATIONAL3                     0x89

         #define KEY_INTERNATIONAL4                     0x8A

         #define KEY_INTERNATIONAL5                     0x8B

         #define KEY_INTERNATIONAL6                     0x8C

         #define KEY_INTERNATIONAL7                     0x8D

         #define KEY_INTERNATIONAL8                     0x8E

         #define KEY_INTERNATIONAL9                     0x8F

         #define KEY_LANG1                              0x90

         #define KEY_LANG2                              0x91

         #define KEY_LANG3                              0x92

         #define KEY_LANG4                              0x93

         #define KEY_LANG5                              0x94

         #define KEY_LANG6                              0x95

         #define KEY_LANG7                              0x96

         #define KEY_LANG8                              0x97

         #define KEY_LANG9                              0x98

         #define KEY_ALTERNATE_ERASE                    0x99

         #define KEY_SYSREQ                             0x9A

         #define KEY_CANCEL                             0x9B

         #define KEY_CLEAR                              0x9C

         #define KEY_PRIOR                              0x9D

         #define KEY_RETURN                             0x9E

         #define KEY_SEPARATOR                          0x9F

         #define KEY_OUT                                0xA0

         #define KEY_OPER                               0xA1

         #define KEY_CLEAR_AGAIN                        0xA2

         #define KEY_CRSEL                              0xA3

         #define KEY_EXSEL                              0xA4

         #define KEY_KEYPAD_00                          0xB0

         #define KEY_KEYPAD_000                         0xB1

         #define KEY_THOUSANDS_SEPARATOR                0xB2

         #define KEY_DECIMAL_SEPARATOR                  0xB3

         #define KEY_CURRENCY_UNIT                      0xB4

         #define KEY_CURRENCY_SUB_UNIT                  0xB5

         #define KEY_KEYPAD_OPARENTHESIS                0xB6

         #define KEY_KEYPAD_CPARENTHESIS                0xB7

         #define KEY_KEYPAD_OBRACE                      0xB8

         #define KEY_KEYPAD_CBRACE                      0xB9

         #define KEY_KEYPAD_TAB                         0xBA

         #define KEY_KEYPAD_BACKSPACE                   0xBB

         #define KEY_KEYPAD_A                           0xBC

         #define KEY_KEYPAD_B                           0xBD

         #define KEY_KEYPAD_C                           0xBE

         #define KEY_KEYPAD_D                           0xBF

         #define KEY_KEYPAD_E                           0xC0

         #define KEY_KEYPAD_F                           0xC1

         #define KEY_KEYPAD_XOR                         0xC2

         #define KEY_KEYPAD_CARET                       0xC3

         #define KEY_KEYPAD_PERCENT                     0xC4

         #define KEY_KEYPAD_LESS                        0xC5

         #define KEY_KEYPAD_GREATER                     0xC6

         #define KEY_KEYPAD_AMPERSAND                   0xC7

         #define KEY_KEYPAD_LOGICAL_AND                 0xC8

         #define KEY_KEYPAD_VERTICAL_BAR                0xC9

         #define KEY_KEYPAD_LOGIACL_OR                  0xCA

         #define KEY_KEYPAD_COLON                       0xCB

         #define KEY_KEYPAD_NUMBER_SIGN                 0xCC

         #define KEY_KEYPAD_SPACE                       0xCD

         #define KEY_KEYPAD_AT                          0xCE

         #define KEY_KEYPAD_EXCLAMATION_MARK            0xCF

         #define KEY_KEYPAD_MEMORY_STORE                0xD0

         #define KEY_KEYPAD_MEMORY_RECALL               0xD1

         #define KEY_KEYPAD_MEMORY_CLEAR                0xD2

         #define KEY_KEYPAD_MEMORY_ADD                  0xD3

         #define KEY_KEYPAD_MEMORY_SUBTRACT             0xD4

         #define KEY_KEYPAD_MEMORY_MULTIPLY             0xD5

         #define KEY_KEYPAD_MEMORY_DIVIDE               0xD6

         #define KEY_KEYPAD_PLUSMINUS                   0xD7

         #define KEY_KEYPAD_CLEAR                       0xD8

         #define KEY_KEYPAD_CLEAR_ENTRY                 0xD9

         #define KEY_KEYPAD_BINARY                      0xDA

         #define KEY_KEYPAD_OCTAL                       0xDB

         #define KEY_KEYPAD_DECIMAL                     0xDC

         #define KEY_KEYPAD_HEXADECIMAL                 0xDD

         #define KEY_LEFTCONTROL                        0xE0

         #define KEY_LEFTSHIFT                          0xE1

         #define KEY_LEFTALT                            0xE2

         #define KEY_LEFT_GUI                           0xE3

         #define KEY_RIGHTCONTROL                       0xE4

         #define KEY_RIGHTSHIFT                         0xE5

         #define KEY_RIGHTALT                           0xE6

         #define KEY_RIGHT_GUI                          0xE7

4、恢复正常模式

TPYBoard V10x退出CDC+HID模式的方法有两个，一个是进入安全模式，将boot.py文件的pyb.usb_mode('CDC+HID'）注释掉，另一种是恢复出厂设置，这种方法是按住usr键，按一下reset，然后led2和led3交替亮，当两个灯交替亮到三次，且均亮起时，松开usr，两个灯会快闪多次，然后TPYBV101恢复到出厂设置，此时main.py里的内容也都清空了。