SLAA450G April   2010  – April 2020

 

  1.   Creating a Custom Flash-Based Bootloader (BSL)
    1.     Trademarks
    2. 1 5xx and 6xx Bootloader Customization
      1. 1.1 BSL Memory Layout
        1. 1.1.1 Z-Area
        2. 1.1.2 BSL Reserved Memory Locations
      2. 1.2 Device Start-up Sequence
        1. 1.2.1 BSL Protect Function
          1. 1.2.1.1 Protection of BSL Memory
          2. 1.2.1.2 Checking for BSL Invoke
      3. 1.3 TI-Supplied BSL Software
        1. 1.3.1 Software Overview
        2. 1.3.2 Software File Details
          1. 1.3.2.1 BSL430_Low_Level_Init.s43 (IAR) / BSL430_Low_Level_Init.asm (CCS)
          2. 1.3.2.2 BSL_Device_File.h
          3. 1.3.2.3 lnk430FXXXX_BSL_AREA.xcl (IAR) / MSP430Fxxxx_BSL.cmd (CCS)
        3. 1.3.3 Known Limitations in CCS CSL Code Example
          1. 1.3.3.1 Memory Allocation of BSL Code Under Linker Command File
          2. 1.3.3.2 BSL Functions Supported in the Default Setting Project
          3. 1.3.3.3 How to Accomodate Full Function of BSL
          4. 1.3.3.4 Using Modified boot_hook.h and boot.c (CCS Only)
      4. 1.4 Creation of Custom Peripheral Interface
        1. 1.4.1 PI_init ()
        2. 1.4.2 PI_receivePacket()
        3. 1.4.3 PI_sendData(int bufSize)
      5. 1.5 BSL Development and Debug
        1. 1.5.1 Development and Testing
        2. 1.5.2 Special Notes and Tips
        3. 1.5.3 USB BSL External Oscillator Frequency
    3. 2 G2xx Bootloader Creation and Customization
      1. 2.1 Target System Specification
      2. 2.2 BSL Specification
        1. 2.2.1 Functionality
          1. 2.2.1.1 Entry Sequence
          2. 2.2.1.2 Synchronization
          3. 2.2.1.3 Erasing Previous Flash Content
          4. 2.2.1.4 Receiving and Writing New User Data
          5. 2.2.1.5 Data Verification
        2. 2.2.2 Memory Footprint
        3. 2.2.3 Peripherals
      3. 2.3 Implementation
        1. 2.3.1 BSL Assembler Code
          1. 2.3.1.1 Save DCO Calibration Data
          2. 2.3.1.2 Linker Command File
            1. 2.3.1.2.1 Locating the Linker Command File
            2. 2.3.1.2.2 Modify Linker File
            3. 2.3.1.2.3 Force the IDE to Use Custom Linker File
          3. 2.3.1.3 Project Settings
        2. 2.3.2 User Application
      4. 2.4 BSL Operation
        1. 2.4.1 Hardware Setup
        2. 2.4.2 Connection to Host
          1. 2.4.2.1 Determining COM Port
          2. 2.4.2.2 Setup of COM Port
        3. 2.4.3 Operate BSL - Standard Sequence
        4. 2.4.4 Create New Code to Download Through BSL
          1. 2.4.4.1 Create Custom Application
          2. 2.4.4.2 Save Calibration Data
          3. 2.4.4.3 Make User Application Code a BSL Update File
            1. 2.4.4.3.1 Using CCS
            2. 2.4.4.3.2 Using IAR
          4. 2.4.4.4 Obtaining XOR Checksum
            1. 2.4.4.4.1 Send User Data
            2. 2.4.4.4.2 Read Checksum
            3. 2.4.4.4.3 Send Acquired Checksum
            4. 2.4.4.4.4 Verify Data
            5. 2.4.4.4.5 Save Checksum
        5. 2.4.5 Getting Ready for Production
    4. 3 Frequently Asked Questions (FAQ)
  2.   Revision History

1.2.1.2 Checking for BSL Invoke

The BSL Protect function also must indicate whether the BSL or application code (if present) should start. This selection is made by setting bits in R12 to these defined values:

Bit 0

0: Indicates that the JTAG state should be determined based on JTAG Key state.

1: Overrides the JTAG Key, keeping JTAG open (used primarily for debugging the BSL).

Bit 1

0: Indicates the BSL should not be started.

1: Indicates the BSL should be started by loading the value in the BSL Start Vector to the PC.

The method for determining whether the BSL should be invoked is entirely dependent on the BSL Protect function. TI-supplied UART BSLs check the SYSBSLIND bit to check for the occurrence of a specific pin-toggle sequence. The TI-supplied USB BSLs, however, have an entirely different start-up criteria based on their application requirements: if USB power is present and the device is blank, the BSL Protect function indicates that the BSL should start, so the blank device may be programmed through USB. However, in a custom BSL, almost any criteria could be used, such as checking the user code against a known CRC value to make sure that only correctly programmed user code begins execution.