SPRZ423K October   2014  – May 2024 TMS320F28075 , TMS320F28075-Q1 , TMS320F28076

 

  1.   1
  2.   Abstract
  3. 1Usage Notes and Advisories Matrices
    1. 1.1 Usage Notes Matrix
    2. 1.2 Advisories Matrix
  4. 2Nomenclature, Package Symbolization, and Revision Identification
    1. 2.1 Device and Development Support Tool Nomenclature
    2. 2.2 Devices Supported
    3. 2.3 Package Symbolization and Revision Identification
  5. 3Silicon Revision C Usage Notes and Advisories
    1. 3.1 Silicon Revision C Usage Notes
      1. 3.1.1 PIE: Spurious Nested Interrupt After Back-to-Back PIEACK Write and Manual CPU Interrupt Mask Clear
      2. 3.1.2 Caution While Using Nested Interrupts
      3. 3.1.3 SYS/BIOS: Version Implemented in Device ROM is not Maintained
      4. 3.1.4 SDFM: Use Caution While Using SDFM Under Noisy Conditions
      5. 3.1.5 McBSP: XRDY Bit can Hold the Not-Ready Status (0) if New Data is Written to the DX1 Register Without Verifying if the XRDY Bit is in its Ready State (1)
    2. 3.2 Silicon Revision C Advisories
      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
      23.      Advisory
      24.      Advisory
      25.      Advisory
      26.      Advisory
      27.      Advisory
      28.      Advisory
      29.      Advisory
      30.      Advisory
      31.      Advisory
      32.      Advisory
      33.      Advisory
      34.      Advisory
      35.      Advisory
      36.      Advisory
  6. 4Silicon Revision B Usage Notes and Advisories
    1. 4.1 Silicon Revision B Usage Notes
    2. 4.2 Silicon Revision B Advisories
      1.      Advisory
      2.      Advisory
      3.      Advisory
      4.      Advisory
      5.      Advisory
      6.      Advisory
      7.      Advisory
      8.      Advisory
      9.      Advisory
  7. 5Documentation Support
  8. 6Trademarks
  9. 7Revision History

Advisory

SYSTEM: Multiple Successive Writes to CLKSRCCTL1 Can Cause a System Hang

Revisions Affected

B, C

Details

When the CLKSRCCTL1 register is written more than once without delay between writes, the system can hang and can only be recovered by an external XRS reset or Watchdog reset. The occurrence of this condition depends on the clock ratio between SYSCLK and the clock selected by OSCCLKSRCSEL, and may not occur every time.

If this issue is encountered while using the debugger, then after hitting pause, the program counter will be at the Boot ROM reset vector.

Implementing the workaround will avoid this condition for any SYSCLK to OSCCLK ratio.

Workarounds

Add a software delay of 300 SYSCLK cycles using an NOP instruction after every write to the CLKSRCCTL1 register.

Example:


ClkCfgRegs.CLKSRCCTL1.bit.INTOSC2OFF=0;         // Turn on INTOSC2
asm("  RPT #250 || NOP");                       // Delay of 250 SYSCLK Cycles
asm("  RPT #50 || NOP");                        // Delay of 50 SYSCLK Cycles
ClkCfgRegs.CLKSRCCTL1.bit.OSCCLKSRCSEL = 0;     // Clk Src = INTOSC2
asm("  RPT #250 || NOP");                       // Delay of 250 SYSCLK Cycles
asm("  RPT #50 || NOP");                        // Delay of 50 SYSCLK Cycles

C2000Ware_3_00_00_00 and later revisions will have this workaround implemented.