SWRA779 September   2023 CC3300 , CC3301

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Main Features
    1. 2.1 Dual Host Interface
    2. 2.2 Shared Host Interface
    3. 2.3 Autonomous Mode
    4. 2.4 Host Interrupt
      1. 2.4.1 Out-of-Band Interrupt
      2. 2.4.2 In-Band Interrupt
  6. 3Interfaces
    1. 3.1 Introduction
    2. 3.2 SDIO Interface
      1. 3.2.1 SDIO Overview
      2. 3.2.2 SDIO Flow Control
    3. 3.3 SPI Interface
      1. 3.3.1 SPI Overview
      2. 3.3.2 SPI Configuration
      3. 3.3.3 SPI Flow Control
    4. 3.4 Uart Interface
      1. 3.4.1 UART Overview
      2. 3.4.2 UART Configuration
      3. 3.4.3 UART Flow Control
    5. 3.5 Pin Count Options
  7. 4Host Communication
    1. 4.1 Protocol Overview
    2. 4.2 SDIO Wrapper
    3. 4.3 SPI Wrapper
  8. 5Boot Flow
    1. 5.1 SDIO
    2. 5.2 SPI

3.2.2 SDIO Flow Control

SDIO flow control is part of the specification. SDIO DAT0 data line is used to implement the busy signal to the host controller. Assertion of this line (pulling the pin low) would get interpreted by the host controller as the device is busy and in return the host controller would wait with its write/read operations.

Like in autonomous mode, the flow control is a real time mechanism and can even be triggered in between SDIO blocks, making it optimal in terms of power consumption.

This method is also used for autonomous mode implementation to indicate when the peripheral is ready and when it is not ready.