SPRZ408D June   2014  – June 2021 AM4372 , AM4376 , AM4377 , AM4378 , AM4379

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Device and Development Support Tool Nomenclature
    2. 1.2 Revision Identification
  3. 2All Errata Listed With Silicon Revision Number
  4. 3Usage Notes and Known Design Exceptions to Functional Specifications
    1. 3.1 Usage Notes
      1. 3.1.1 LPDDR2/DDR3: JEDEC Compliance for Minimum Self-Refresh Command Interval
      2. 3.1.2 DDR3/DDR3L: JEDEC Specification Violation for DDR3 RESET Signal When Implementing RTC+DDR Mode
    2. 3.2 Known Design Exceptions to Functional Specifications
      1. 3.2.1 Advisory List
      2.      Advisory 1
      3.      Advisory 2
      4.      Advisory 3
      5.      Advisory 4
      6.      Advisory 5
      7.      Advisory 6
      8.      Advisory 7
      9.      Advisory 8
      10.      Advisory 9
      11.      Advisory 10
      12.      Advisory 11
      13.      Advisory 12
      14.      Advisory 13
      15.      Advisory 14
      16.      Advisory 15
      17.      Advisory 16
      18.      Advisory 17
      19.      Advisory 19
      20.      Advisory 20
      21.      Advisory 21
      22.      Advisory 22
      23.      Advisory 24
      24.      Advisory 25
      25.      Advisory 26
      26.      Advisory 27
      27.      Advisory 28
      28.      i2223
      29.      i2224
      30.      i912
      31.      i2225
      32.      i2226
  5. 4Revision History

Advisory 21

UART: UART0-5 Do Not Acknowledge Idle Request After DMA Has Been Enabled

Revisions Affected

1.1, 1.2

Details

All UART modules (UART0-5) in the device do not acknowledge an idle request after enabling the module's DMA feature, even if the DMA is subsequently disabled. Thus, the UART module cannot be clock idled after enabling DMA with

  • UART_SCR.DMAMODECTL = 1 and UART_SCR.DMAMODE2 != 0

    OR

  • UART_SCR.DMAMODECTL = 0 and UART_FCR.DMA_MODE = 1

A consequence of this is that CM_WKUP_UARTx_CLKCTRL will remain in transition when trying to disable the module (UARTx_CLKCTRL = 0x10000) and the associated CLKACTIVITY bit will remain active.

Workaround

Initiating a soft reset (UART_SYSC.SOFTRESET = 1) will allow the module to acknowledge the idle request.