SLAU533D September   2013  – April 2017

 

  1.   MSP430F5529 LaunchPad™ Development Kit (MSP‑EXP430F5529LP)
    1.     Trademarks
    2. 1 Getting Started
      1. 1.1 Key Features
      2. 1.2 Kit Contents
      3. 1.3 Out-of-Box Experience
        1. 1.3.1 Step 1: Install a Software Development Platform
        2. 1.3.2 Step 2: Connect the Hardware
        3. 1.3.3 Step 3: Verify the storage volume has been loaded
        4. 1.3.4 Step 4: Open a text editor, and press the buttons
        5. 1.3.5 Step 5: Customize the strings
    3. 2 Hardware
      1. 2.1 Block Diagram
      2. 2.2 Hardware Features
        1. 2.2.1 MSP430F5529
        2. 2.2.2 eZ-FET lite Onboard Emulator
        3. 2.2.3 Integrated Full-Speed USB Hub
        4. 2.2.4 Power
        5. 2.2.5 Clocking
        6. 2.2.6 Application (or "Backchannel") UART
        7. 2.2.7 Emulator and Target Isolation Jumper Block
        8. 2.2.8 Isolation Jumper Block: 3.3-V and 5-V Jumpers
        9. 2.2.9 Isolation Jumper Block: Emulator Connection and Application UART
      3. 2.3 Measure Current Draw of MSP430 MCU
      4. 2.4 Using an External Power Source
        1. 2.4.1 External 3.3-V Power Source
        2. 2.4.2 External 5-V Power Source Without USB Connection
        3. 2.4.3 External 5-V Power Source With USB Connection
      5. 2.5 Using the eZ-FET lite Emulator With a Different Target
      6. 2.6 USB BSL Button
      7. 2.7 BoosterPack Plug-in Module Pinout
      8. 2.8 Design Files
      9. 2.9 Hardware Change Log
    4. 3 Software Examples
      1. 3.1 MSP430 Software Libraries: driverlib and the USB API
      2. 3.2 Viewing the Code
        1. 3.2.1 CCS
        2. 3.2.2 IAR
      3. 3.3 Example Project Software Organization
      4. 3.4 USB Configuration Files
      5. 3.5 Out-of-Box Experience: emulStorageKeyboard
        1. 3.5.1  Flowchart
        2. 3.5.2  Pre-Initialization
        3. 3.5.3  Initialization
          1. 3.5.3.1 Configuring the Keyboard
          2. 3.5.3.2 Configuring the MSC Interface
        4. 3.5.4  Handling SCSI Commands
        5. 3.5.5  LPM0 Entry
        6. 3.5.6  LPM0 Exit
        7. 3.5.7  Emulated Storage Volume
        8. 3.5.8  Sending Data as a USB Keyboard
        9. 3.5.9  Properly Handling USB Unplug Events
        10. 3.5.10 Non-Maskable Interrupt (NMI) Vector
      6. 3.6 Example: simpleUsbBackchannel
        1. 3.6.1 What It Does
        2. 3.6.2 Installing the CDC Interface
        3. 3.6.3 Operating the Example
        4. 3.6.4 Backchannel UART Library: bcUart.c, bcUart.h
        5. 3.6.5 Code Description: Initialization
          1. 3.6.5.1 Stopping the Watchdog
          2. 3.6.5.2 Configuring VCORE
          3. 3.6.5.3 Configuring Clocks
          4. 3.6.5.4 Configuring Ports
          5. 3.6.5.5 Initializing the Backchannel UART
          6. 3.6.5.6 Configuring USB
        6. 3.6.6 Code Description: Main Loop
        7. 3.6.7 Modifying to Use an HID-Datapipe Interface
      7. 3.7 Starting Device Manager
    5. 4 Additional Resources
      1. 4.1 LaunchPad Development Kit Websites
      2. 4.2 Information on the MSP430F5529
      3. 4.3 Download CCS, IAR, mspgcc, or Energia
      4. 4.4 USB Developers Package
      5. 4.5 MSP430Ware and TI Resource Explorer
      6. 4.6 F5529 Code Examples
      7. 4.7 MSP430 Application Notes
      8. 4.8 TI E2E Community
      9. 4.9 Community at Large
    6. 5 FAQs
    7. 6 Schematics
  2.   Revision History

3.5.4 Handling SCSI Commands

The first item in the main loop is a call to USBMSC_poll().

__disable_interrupt(); if ((USBMSC_poll() == kUSBMSC_okToSleep) && !charLeftToSend && !bButton1Pressed && !bButton2Pressed) { __bis_SR_register(LPM0_bits + GIE); } __enable_interrupt();

Notice all of the code surrounding USBMSC_poll(); this is discussed in Section 3.5.5.

Every USB application with an MSC interface must call this function regularly to check for any SCSI commands received from the host. The USB MSC interface is essentially a carrier for the same SCSI commands used with many non-USB storage devices that are commonly used with computers. In other words, the interface is essentially "SCSI-over-USB".

USBMSC_poll() automatically handles all SCSI commands except READ and WRITE. These two require media access. The developer might choose among a wide variety of media types, and there are many different file system "middleware" offerings on the market. To preserve these options for the developer, the MSC API lets the application access the media. mscProcessBuffer() is the function that serves this function for the software demo; it receives a block buffer from the API and exchanges data between this buffer and the media (see Section 3.5.7 for more information).

Most MSC applications need this exact same block within the main loop, except that the checking of the charLeftToSend and button-pressed flags are specific to this demo application.