SPRZ171T December   2004  – September 2020 SM320F2801-EP , SM320F2808-EP , TMS320F2801 , TMS320F2801-Q1 , TMS320F28015 , TMS320F28016 , TMS320F28016-Q1 , TMS320F2802 , TMS320F2802-Q1 , TMS320F2806 , TMS320F2806-Q1 , TMS320F2808 , TMS320F2808-Q1 , TMS320F2809 , TMS320F2809-Q1

 

  1. 1Introduction
  2. 2Device and Development Tool Support Nomenclature
  3. 3Device Markings
  4. 4Silicon Change Overview
  5. 5Usage Notes and Known Design Exceptions to Functional Specifications
    1. 5.1 Usage Notes
      1. 5.1.1 PIE: Spurious Nested Interrupt After Back-to-Back PIEACK Write and Manual CPU Interrupt Mask Clear Usage Note
    2. 5.2 Known Design Exceptions to Functional Specifications
      1.      Advisory
      2.      Advisory
      3.      Advisory
      4.      Advisory
      5.      Advisory
      6.      Advisory
      7.      Advisory
      8.      Advisory
      9.      Advisory
      10.      Advisory
      11.      Advisory
      12.      Advisory
      13.      Advisory
      14.      Advisory
      15.      Advisory
      16.      Advisory
      17.      Advisory
      18.      Advisory
      19.      Advisory
      20.      Advisory
      21.      Advisory
      22.      Advisory
  6. 6Documentation Support
  7. 7Trademarks
  8. 8Revision History

Advisory

Memory: Prefetching Beyond Valid Memory

Revision(s) Affected

0, A on F2809 silicon

0, A on C280x silicon

0, A, B, C on F2801, F2802, F2806, F2808, and F2801x silicon

Details

The C28x CPU prefetches instructions beyond those currently active in its pipeline. If the prefetch occurs past the end of valid memory, then the CPU may receive an invalid opcode.

Workaround

The prefetch queue is 8x16 words in depth. Therefore, code should not come within 8 words of the end of valid memory. This restriction applies to all memory regions and all memory types (Flash/ROM, OTP, SARAM) on the device. Prefetching across the boundary between two valid memory blocks is ok.

Example 1: M1 ends at address 0x7FF and is not followed by another memory block. Code in M1 should be stored no farther than address 0x7F7. Addresses 0x7F8-0x7FF should not be used for code.

Example 2: M0 ends at address 0x3FF and valid memory (M1) follows it. Code in M0 can be stored up to and including address 0x3FF. Code can also cross into M1 up to and including address 0x7F7.