Stratix® 10 Hard Processor System Technical Reference Manual

ID 683222
Date 8/15/2024
Public
Document Table of Contents

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