@Yvette 其实上午弄过Karabiner，但是不得要领，不知道怎么映射。刚才研究了一下，成功搞定，其实也很简单，就是把小键盘上的数字键映射成大键盘上的数字键。

我做的private.xml代码如下：
<?xml version="1.0"?>
<root>
<item>
<name>Change KeyPad 0 to Num 0</name>
<identifier>private.change_keypad0_to_num0</identifier>
<autogen>__KeyToKey__ KeyCode::KEYPAD_0, KeyCode::KEY_0</autogen>
</item>

<item>
<name>Change KeyPad 1 to Num 1</name>
<identifier>private.change_keypad1_to_num1</identifier>
<autogen>__KeyToKey__ KeyCode::KEYPAD_1, KeyCode::KEY_1</autogen>
</item>

<item>
<name>Change KeyPad 2 to Num 2</name>
<identifier>private.change_keypad2_to_num2</identifier>
<autogen>__KeyToKey__ KeyCode::KEYPAD_2, KeyCode::KEY_2</autogen>
</item>

<item>
<name>Change KeyPad 3 to Num 3</name>
<identifier>private.change_keypad3_to_num3</identifier>
<autogen>__KeyToKey__ KeyCode::KEYPAD_3, KeyCode::KEY_3</autogen>
</item>

<item>
<name>Change KeyPad 4 to Num 4</name>
<identifier>private.change_keypad4_to_num4</identifier>
<autogen>__KeyToKey__ KeyCode::KEYPAD_4, KeyCode::KEY_4</autogen>
</item>

<item>
<name>Change KeyPad 5 to Num 5</name>
<identifier>private.change_keypad5_to_num5</identifier>
<autogen>__KeyToKey__ KeyCode::KEYPAD_5, KeyCode::KEY_5</autogen>
</item>

<item>
<name>Change KeyPad 6 to Num 6</name>
<identifier>private.change_keypad6_to_num6</identifier>
<autogen>__KeyToKey__ KeyCode::KEYPAD_6, KeyCode::KEY_6</autogen>
</item>

<item>
<name>Change KeyPad 7 to Num 7</name>
<identifier>private.change_keypad7_to_num7</identifier>
<autogen>__KeyToKey__ KeyCode::KEYPAD_7, KeyCode::KEY_7</autogen>
</item>

<item>
<name>Change KeyPad 8 to Num 8</name>
<identifier>private.change_keypad8_to_num8</identifier>
<autogen>__KeyToKey__ KeyCode::KEYPAD_8, KeyCode::KEY_8</autogen>
</item>

<item>
<name>Change KeyPad 9 to Num 9</name>
<identifier>private.change_keypad9_to_num9</identifier>
<autogen>__KeyToKey__ KeyCode::KEYPAD_9, KeyCode::KEY_9</autogen>
</item>

<item>
<name>Change KeyPad Enter to Return</name>
<identifier>private.change_keypadEnter_to_return</identifier>
<autogen>__KeyToKey__ KeyCode::ENTER, KeyCode::RETURN</autogen>
</item>

</root>


我参考的资料：
How to add your own settings： https://pqrs.org/osx/karabiner/document.html.en#privatexml
private.xml参考手册： https://pqrs.org/osx/karabiner/xml.html.en