SPRAD59 October   2023 TMS320F280039

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1 Introduction
  5. 2 Key Differences Between DCAN and MCAN
  6. 3 Module Initialization
    1. 3.1 DCAN Initialization
    2. 3.2 MCAN Initialization
    3. 3.3 Initialization sequence
    4. 3.4 Code Snippets for Module Initialization
  7. 4 Bit Timing Configuration
  8. 5 Message RAM Configuration
  9. 6 Interrupt handling
    1. 6.1 MCAN Interrupt Sources
    2. 6.2 DCAN Interrupt Handling
    3. 6.3 MCAN Interrupt Handling
  10. 7 Transmitting data
    1. 7.1 Basic Transmission Process
      1. 7.1.1 Transmission with DCAN
      2. 7.1.2 Transmission with MCAN
    2. 7.2 MCAN Vs DCAN Transmit Procedural Differences
    3. 7.3 MCAN Transmit Concepts
      1. 7.3.1 Tx Event FIFO
  11. 8 Receiving Data
    1. 8.1 Introduction to Reception
    2. 8.2 Basic Reception Process
      1. 8.2.1 DCAN Reception
      2. 8.2.2 MCAN Reception
    3. 8.3 Filter Elements
      1. 8.3.1 Filter Element Structure
    4. 8.4 Rx Buffer
      1. 8.4.1 Receiving in Rx Buffer
    5. 8.5 Rx FIFO
      1. 8.5.1 Receiving in Rx FIFO
    6. 8.6 Receiving High Priority Messages
  12. 9 Avoiding network errors
  13. 10References

8.4.1 Receiving in Rx Buffer

In case of filtering for Rx Buffers, a filter element can be configured to store a frame with matching ID defined by Standard ID1, in a Rx Buffer Element for which the number is defined by Standard ID2. Consequently, there has to be one Filter Element (std/ext) for each Rx Buffer Element. It is NOT possible to use any filter types to store frames in the Rx Buffer.

An interrupt can be generated when a new message is received in a dedicated Rx Buffer. There are two registers MCAN_NDAT1 and MCAN_NDAT2, with a bit corresponding to each of the possible 64 Rx Buffer elements, which is set on receiving a new frame in the particular buffer element. This new message can be read from the Message RAM using Driverlib API after which the New Data Flag needs to be cleared. As long as the New Data Flag is set, the Rx Buffer Element does not receive new data, and the corresponding filter element is disabled.

GUID-20231010-SS0I-PXGB-JQKS-THVX0KTX3FTZ-low.png Figure 8-3 Reception using Rx Buffer