FX3 DMA生产者消费者ID代表的含义

　　在开发FX3的时候，觉得赛普拉斯的库注释太少，很多时候无法理解代码含义。由于使用DMA，需要理解DMA生产者消费者代表的含义，经过多方查找，决定记录下来。

在cyu3dma.h中对SocketID进行了枚举，以下是其具体代码。

 typedef enum CyU3PDmaSocketId_t
 {
     CY_U3P_LPP_SOCKET_I2S_LEFT = 0x0000,        /**< Left channel output to I2S port. */
     CY_U3P_LPP_SOCKET_I2S_RIGHT,                /**< Right channel output to I2S port. */
     CY_U3P_LPP_SOCKET_I2C_CONS,                 /**< Outgoing data to I2C slave. */
     CY_U3P_LPP_SOCKET_UART_CONS,                /**< Outgoing data to UART peer. */
     CY_U3P_LPP_SOCKET_SPI_CONS,                 /**< Outgoing data to SPI slave. */
     CY_U3P_LPP_SOCKET_I2C_PROD,                 /**< Incoming data from I2C slave. */
     CY_U3P_LPP_SOCKET_UART_PROD,                /**< Incoming data from UART peer. */
     CY_U3P_LPP_SOCKET_SPI_PROD,                 /**< Incoming data from SPI slave. */

     CY_U3P_PIB_SOCKET_0 = 0x0100,               /**< P-port socket number 0. */
     CY_U3P_PIB_SOCKET_1,                        /**< P-port socket number 1. */
     CY_U3P_PIB_SOCKET_2,                        /**< P-port socket number 2. */
     CY_U3P_PIB_SOCKET_3,                        /**< P-port socket number 3. */
     CY_U3P_PIB_SOCKET_4,                        /**< P-port socket number 4. */
     CY_U3P_PIB_SOCKET_5,                        /**< P-port socket number 5. */
     CY_U3P_PIB_SOCKET_6,                        /**< P-port socket number 6. */
     CY_U3P_PIB_SOCKET_7,                        /**< P-port socket number 7. */
     CY_U3P_PIB_SOCKET_8,                        /**< P-port socket number 8. */
     CY_U3P_PIB_SOCKET_9,                        /**< P-port socket number 9. */
     CY_U3P_PIB_SOCKET_10,                       /**< P-port socket number 10. */
     CY_U3P_PIB_SOCKET_11,                       /**< P-port socket number 11. */
     CY_U3P_PIB_SOCKET_12,                       /**< P-port socket number 12. */
     CY_U3P_PIB_SOCKET_13,                       /**< P-port socket number 13. */
     CY_U3P_PIB_SOCKET_14,                       /**< P-port socket number 14. */
     CY_U3P_PIB_SOCKET_15,                       /**< P-port socket number 15. */
     CY_U3P_PIB_SOCKET_16,                       /**< P-port socket number 16. */
     CY_U3P_PIB_SOCKET_17,                       /**< P-port socket number 17. */
     CY_U3P_PIB_SOCKET_18,                       /**< P-port socket number 18. */
     CY_U3P_PIB_SOCKET_19,                       /**< P-port socket number 19. */
     CY_U3P_PIB_SOCKET_20,                       /**< P-port socket number 20. */
     CY_U3P_PIB_SOCKET_21,                       /**< P-port socket number 21. */
     CY_U3P_PIB_SOCKET_22,                       /**< P-port socket number 22. */
     CY_U3P_PIB_SOCKET_23,                       /**< P-port socket number 23. */
     CY_U3P_PIB_SOCKET_24,                       /**< P-port socket number 24. */
     CY_U3P_PIB_SOCKET_25,                       /**< P-port socket number 25. */
     CY_U3P_PIB_SOCKET_26,                       /**< P-port socket number 26. */
     CY_U3P_PIB_SOCKET_27,                       /**< P-port socket number 27. */
     CY_U3P_PIB_SOCKET_28,                       /**< P-port socket number 28. */
     CY_U3P_PIB_SOCKET_29,                       /**< P-port socket number 29. */
     CY_U3P_PIB_SOCKET_30,                       /**< P-port socket number 30. */
     CY_U3P_PIB_SOCKET_31,                       /**< P-port socket number 31. */

     CY_U3P_SIB_SOCKET_0 = 0x0200,               /**< S-port socket number 0. */
     CY_U3P_SIB_SOCKET_1,                        /**< S-port socket number 1. */
     CY_U3P_SIB_SOCKET_2,                        /**< S-port socket number 2. */
     CY_U3P_SIB_SOCKET_3,                        /**< S-port socket number 3. */
     CY_U3P_SIB_SOCKET_4,                        /**< S-port socket number 4. */
     CY_U3P_SIB_SOCKET_5,                        /**< S-port socket number 5. */

     //U-port是指endpoint socket
     CY_U3P_UIB_SOCKET_CONS_0 = 0x0300,          /**< U-port output socket number 0. */
     CY_U3P_UIB_SOCKET_CONS_1,                   /**< U-port output socket number 1. */
     CY_U3P_UIB_SOCKET_CONS_2,                   /**< U-port output socket number 2. */
     CY_U3P_UIB_SOCKET_CONS_3,                   /**< U-port output socket number 3. */
     CY_U3P_UIB_SOCKET_CONS_4,                   /**< U-port output socket number 4. */
     CY_U3P_UIB_SOCKET_CONS_5,                   /**< U-port output socket number 5. */
     CY_U3P_UIB_SOCKET_CONS_6,                   /**< U-port output socket number 6. */
     CY_U3P_UIB_SOCKET_CONS_7,                   /**< U-port output socket number 7. */
     CY_U3P_UIB_SOCKET_CONS_8,                   /**< U-port output socket number 8. */
     CY_U3P_UIB_SOCKET_CONS_9,                   /**< U-port output socket number 9. */
     CY_U3P_UIB_SOCKET_CONS_10,                  /**< U-port output socket number 10. */
     CY_U3P_UIB_SOCKET_CONS_11,                  /**< U-port output socket number 11. */
     CY_U3P_UIB_SOCKET_CONS_12,                  /**< U-port output socket number 12. */
     CY_U3P_UIB_SOCKET_CONS_13,                  /**< U-port output socket number 13. */
     CY_U3P_UIB_SOCKET_CONS_14,                  /**< U-port output socket number 14. */
     CY_U3P_UIB_SOCKET_CONS_15,                  /**< U-port output socket number 15. */

     CY_U3P_UIB_SOCKET_PROD_0 = 0x400,           /**< U-port input socket number 0. */
     CY_U3P_UIB_SOCKET_PROD_1,                   /**< U-port input socket number 1. */
     CY_U3P_UIB_SOCKET_PROD_2,                   /**< U-port input socket number 2. */
     CY_U3P_UIB_SOCKET_PROD_3,                   /**< U-port input socket number 3. */
     CY_U3P_UIB_SOCKET_PROD_4,                   /**< U-port input socket number 4. */
     CY_U3P_UIB_SOCKET_PROD_5,                   /**< U-port input socket number 5. */
     CY_U3P_UIB_SOCKET_PROD_6,                   /**< U-port input socket number 6. */
     CY_U3P_UIB_SOCKET_PROD_7,                   /**< U-port input socket number 7. */
     CY_U3P_UIB_SOCKET_PROD_8,                   /**< U-port input socket number 8. */
     CY_U3P_UIB_SOCKET_PROD_9,                   /**< U-port input socket number 9. */
     CY_U3P_UIB_SOCKET_PROD_10,                  /**< U-port input socket number 10. */
     CY_U3P_UIB_SOCKET_PROD_11,                  /**< U-port input socket number 11. */
     CY_U3P_UIB_SOCKET_PROD_12,                  /**< U-port input socket number 12. */
     CY_U3P_UIB_SOCKET_PROD_13,                  /**< U-port input socket number 13. */
     CY_U3P_UIB_SOCKET_PROD_14,                  /**< U-port input socket number 14. */
     CY_U3P_UIB_SOCKET_PROD_15,                  /**< U-port input socket number 15. */

     CY_U3P_CPU_SOCKET_CONS = 0x3F00,            /**< Socket through which the FX3 CPU receives data. */
     CY_U3P_CPU_SOCKET_PROD                      /**< Socket through which the FX3 CPU produces data. */

 } CyU3PDmaSocketId_t;

其中：

　　LPP_SOCKET是指 外设硬件端口，如CY_U3P_LPP_SOCKET_UART_PROD就代表UART的 RX 端口，而CY_U3P_LPP_SOCKET_UART_CONS就代表TX，因为数据要从TX端口发送。

　　P-PORT 是指FX3中的GPIF端口

　　S-PORT 是指FX3专门为SD/MMC卡准备的端口

　　U-PORT 是指USB端口，或者说是Endpoint Socket端口

　　CPU_SOCKET是指 FX3的CPU所收到的数据储存的端口