Specifications

Physical Layer Simplified Specification Version 4.10

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5.8 Application Specification on Function Extension

All application specifications defined in this section are assigned to Memory Extension Register Space.

Assignment of Standard Function Code for memory is managed by Table 5-25.

Function Name

Standard Function Code

Power Management Function

0001h

Table 5-25 : Standard Function Code Assignment Table

5.8.1 Power Management Function

5.8.1.1 Abstract of Power Management Function

This Section defines three power management functions on Extension Register.

(1) Features of Power Off Notification

Power Off Notification is defined to ensure higher reliability and safety for data stored in the SD

Memory Card. Host should use Power Off Notification (if card support it) before shut down the card

power to avoid problems likely occurs by sudden power off.

(2) Features of Power Sustenance

Card may request host to sustain card power as much as possible to improve card performance. If

host accept power sustenance, the card may operate even while host does not use the card. Once

host accepts power sustenance, host should keep card power as much as possible until host system

power down.

(3) Features of Power Down Mode

Host may let the card to go into lower power consumption mode while host does not intend to use

the card (Power consumption level is dependent on implementation.). The card can be used again

without re-initialization by retrieving from Power Down Mode (in tran state).

5.8.1.2 Extension Register Set for Power Management

Table 5-26 shows Power Management Register Set consists of 3 bytes registers. Start address of this

Table 5-26 : Power Management Register Set

Figure 5-16 shows Power Management Revision register. Lower 4-bit is assigned to revision of Power

Management Register Set. The first version is indicated to 0000b. Power Management Functions may

be updated with keeping former versions compatibility. Revision will be incremented for every update. A

driver for controlling Power Management register compares card register revision and own driver

revision to determine which functions can be used. This register is read only type and is not affected to