SLAU887 February   2023 MSPM0G1105 , MSPM0G1106 , MSPM0G1107 , MSPM0G1505 , MSPM0G1506 , MSPM0G1507 , MSPM0G3105 , MSPM0G3105-Q1 , MSPM0G3106 , MSPM0G3106-Q1 , MSPM0G3107 , MSPM0G3107-Q1 , MSPM0G3505 , MSPM0G3505-Q1 , MSPM0G3506 , MSPM0G3506-Q1 , MSPM0G3507 , MSPM0G3507-Q1 , MSPM0L1105 , MSPM0L1106 , MSPM0L1303 , MSPM0L1304 , MSPM0L1304-Q1 , MSPM0L1305 , MSPM0L1305-Q1 , MSPM0L1306 , MSPM0L1306-Q1 , MSPM0L1343 , MSPM0L1344 , MSPM0L1345 , MSPM0L1346

 

  1.   Abstract
  2.   Trademarks
  3. 1Overview of BSL Features
  4. 2Terminology
  5. 3BSL Architecture
    1. 3.1 Design
      1. 3.1.1 Timeout Feature
        1. 3.1.1.1 Interface Autodetection
        2. 3.1.1.2 Command Reception
    2. 3.2 BSL Invocation
      1. 3.2.1 Blank Device
      2. 3.2.2 Application Request
      3. 3.2.3 GPIO Based Invocation
      4. 3.2.4 Debug Mailbox Command
      5. 3.2.5 Others
        1. 3.2.5.1 Pre-Boot Application Verification
    3. 3.3 Memory
      1. 3.3.1 SRAM Memory Usage
    4. 3.4 BSL Configuration
    5. 3.5 BSL Status
  6. 4Bootloader Protocol
    1. 4.1 Packet Format
    2. 4.2 UART and I2C BSL Protocol
      1. 4.2.1 BSL Acknowledgment
      2. 4.2.2 Peripheral Configuration
        1. 4.2.2.1 UART
        2. 4.2.2.2 I2C
        3. 4.2.2.3 CRC
    3. 4.3 Bootloader Core Commands
      1. 4.3.1  Connection
      2. 4.3.2  Get Device Info
      3. 4.3.3  Unlock Bootloader
      4. 4.3.4  Program Data
      5. 4.3.5  Program Data Fast
      6. 4.3.6  Readback Data
      7. 4.3.7  Flash Range Erase
      8. 4.3.8  Mass Erase
      9. 4.3.9  Factory Reset
      10. 4.3.10 Standalone Verification
      11. 4.3.11 Start Application
      12. 4.3.12 Change Baud Rate
    4. 4.4 BSL Core Response
      1. 4.4.1 BSL Core Message
      2. 4.4.2 Detailed Error
      3. 4.4.3 Memory Readback
      4. 4.4.4 Device Info
      5. 4.4.5 Standalone Verification
    5. 4.5 Bootloader Security
      1. 4.5.1 Password Protected Commands
        1. 4.5.1.1 Security Alert
      2. 4.5.2 BSL Entry
  7. 5Sample Program Flow with Bootloader
  8. 6Secondary Bootloader
    1. 6.1 Secondary Bootloader Example
  9. 7Interface Plug-in
    1. 7.1 Implementation
      1. 7.1.1 Init
      2. 7.1.2 Receive
      3. 7.1.3 Transmit
      4. 7.1.4 Deinit
      5. 7.1.5 Important Notes
    2. 7.2 Flash Plug-in Type
    3. 7.3 Overriding an Existing Interface
      1. 7.3.1 UART Interface Flash Plug-in Example
  10. 8References
  11. 9Revision History

6 Secondary Bootloader

ROM Bootloader provides an option to use Custom Bootloader. To achieve this, load the custom bootloader in the Main flash memory and register it in the BSL configuration in Non-main Flash. When ROM BSL is invoked next time, it will check for the Secondary Bootloader configuration field and branches to it, and the control is not expected to return back to ROM BSL.

BSL mode configuration in the BCR configuration is applicable for Secondary BSL as well. When this setting is disabled, Secondary BSL will not be invoked.

The flash memory region where the Custom BSL is loaded should be write protected in the BCR configuration, to avoid unintended erase during the bootloading process. Non-main write protection is optional in case of Secondary bootloader use case. But the Secondary Bootloader pointer should be properly restored after erase.

Note:

Erasing the Secondary bootloader could cause a device lock up. Hence it is necessary to write protect the Secondary Bootloader memory region.