I2C初始化

## I2C初始化 ```language void xy_I2C_Init( I2C_TypeDef I2Cx, I2CTransSpeed_TypeDef speed ) ``` ## 参数说明 |参数|功能说明| |-|-|-| |I2Cx|I2C编号| |speed |速率| ## I2C编号 |枚举值| |-|-|-| |I2C1 | |I2C2 | ## 速率 |枚举值| |-|-|-| |I2C_TRANS_SPEED_100K | |I2C_TRANS_SPEED_400K |