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

4.2 UART and I2C BSL Protocol

The data packets of the UART and I2C BSL protocol have the following structure.

  • Header byte indicates the protocol used and the packet type (command or response packet).
  • Length field contains the size of the BSL Core Data in bytes.
  • BSL core data, contains the Command / Response ID and Address, data as needed by the command
  • CRC32 field contains the CRC calculated for the data in BSL core data
PI Code BSL Core Data PI Code
Header (1 byte) Length (2 byte) BSL Core Command/Response CRC32 (4 byte)

Based on the Core data field, the data packet is classified as either Command packet or response packet.

Command packet is the first packet which is transmitted to the BSL. The second packet is the Response packet which is received from the BSL. Response packet contains two components BSL acknowledgment and BSL Core response. In these two, Acknowledgment is received from BSL for every command packet sent. But the BSL core response is not received for every command.

GUID-20221116-SS0I-H7RK-2PQQ-Z7TRRPDDBWW9-low.png Figure 4-1 BSL Protocol