SPMU380 July   2026 TPS25730A

 

  1.   1
  2. 1Read This First
    1. 1.1 About This Manual
    2. 1.2 Notational Conventions
    3. 1.3 Glossary
    4. 1.4 Related Documents
    5. 1.5 Support Resources
    6. 1.6 Trademarks
  3. 2Introduction
    1. 2.1 Purpose and Scope
    2. 2.2 PD Controller Host Interface Description
      1. 2.2.1 Overview
    3. 2.3 Unique Address Interface
      1. 2.3.1 Unique Address Interface Protocol
  4. 3PD Controller Policy Modes
    1. 3.1 Overview
    2. 3.2 Sink Policy Mode
  5. 4Register Overview
    1. 4.1 TPS25730A Registers
  6. 54CC Task Detailed Descriptions
    1. 5.1 Overview
    2. 5.2 PD Message Tasks
      1. 5.2.1 'GSrC' - PD Get Source Capabilities
      2. 5.2.2 'GPPI' - PD Get Port Partner Information
      3. 5.2.3 'MBRd' - Message Buffer Read
    3. 5.3 System Tasks
      1. 5.3.1 'ANeg' - Auto Negotiate Sink Update
      2. 5.3.2 'DBfg' - Clear Dead Battery Flag
  7. 6User Reference
    1. 6.1 AUTO_NEGOTIATE_SINK Register
      1. 6.1.1 AUTO_NEGOTIATE_SINK Usage Example 1
      2. 6.1.2 AUTO_NEGOTIATE_SINK Usage Example 2
      3. 6.1.3 AUTO_NEGOTIATE_SINK Usage Example 3
      4. 6.1.4 AUTO_NEGOTIATE_SINK Usage Example 4
  8. 7Revision History

5.2.3 'MBRd' - Message Buffer Read

Table 5-4 'MBRd' - Read from PD message buffer.
DescriptionThe MBRd Task instructs the PD Controller to read data from the extended message buffer previously received from the Port Partner.
INPUT DATAXBitNameDescription
23ReservedReserved (Write as 0).
22UnlockRxBufferThis input controls whether or not the PD controller unlocks its internal buffer after this Task is completed. It is recommended to unlock the internal buffer as soon as possible to make room for other incoming messages. It is important that the host only set this bit to 1 after it has received an alert that the Rx Buffer is locked.
0bDo not clear the internal buffer, another 'MBRd' Task can be used later.
1bClear the internal buffer after this Task completes and the requested data is in the DATAx register.
21:16DataSizeNumber of data bytes to be read in from the message buffer. Up to 62 bytes can be read at after.
15:0BuffOffsetBuffer Offset. Values 0 to 259 are possible.
OUTPUT DATAXBitNameDescription
511:16DataByte1First Byte of data read at BuffOffset.
15:0MessageSizeSize of message in bytes.
Task CompletionThe MBRd Task completes after buffer data of DataSize at BuffOffset has been read from the message buffer.
Side EffectsNone
Additional InformationThis Task is required for the host to obtain the information from the response due to the usage of the 'GPPI' Task. The PD controller has a single buffer per port that is shared for these messages.