Intel® Agilex™ Hard Processor System Technical Reference Manual

ID 683567
Date 2/14/2023
Public

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16.5.9.5.4. The STANDBY IMMEDIATE Command

This ATA command causes the card device to immediately enter the most aggressive power management mode that still retains internal device context. No data transfer (RW_BLK) is expected for this command.

For card devices that do not provide a power savings mode, the STANDBY IMMEDIATE command returns a successful status indication. The host issues a RW_REG command for the ATA command, and the status is retrieved with the SD/SDIO CMD39 or RW_REG command. Only the status field of the ATA task file contains the success status; there is no error status.

The host controller uses the following settings while sending the RW_REG command for the STANDBY IMMEDIATE ATA command:

  • cmd register setting: data_expected bit set to 0
  • cmdarg register settings:
    • Bit [31] set to 1
    • Bits [7:2] set to 4
    • All other bits set to 0
  • Task file settings:
    • Command field of the ATA task file set to 0xE0
    • Reserved fields of the task file set to 0
  • bytcnt register and block_size field of the blksiz register: set to 16