Specifications

Physical Layer Simplified Specification Version 4.10

111

5. Card Registers

Six registers are defined within the card interface: OCR, CID, CSD, RCA, DSR and SCR. These can be

accessed only by corresponding commands (see Chapter 4.7). The OCR, CID, CSD and SCR registers

carry the card/content specific information, while the RCA and DSR registers are configuration registers

storing actual configuration parameters.

In order to enable future extension, the card shall return 0 in the reserved bits of the registers.

5.1 OCR register

The 32-bit operation conditions register stores the V

voltage profile of the non UHS-II card and V

DD1

voltage profile of the UHS-II card. Additionally, this register includes status information bits. One status

bit is set if the card power up procedure has been finished. This register includes another status bit

indicating the card capacity status after set power up status bit. The OCR register shall be implemented

by the cards.

The 32-bit operation conditions register stores the V

voltage profile of the card. Bit 7 of OCR is newly

defined for Dual Voltage Card and set to 0 in default. If a Dual Voltage Card does not receive CMD8,

OCR bit 7 in the response indicates 0, and the Dual Voltage Card which received CMD8, sets this bit to

Additionally, this register includes 2 more status information bits.

Bit 31 - Card power up status bit, this status bit is set if the card power up procedure has been finished.

Bit 30 - Card Capacity Status bit, 0 indicates that the card is SDSC. 1 indicates that the card is SDHC

or SDXC. The Card Capacity Status bit is valid after the card power up procedure is completed and the

card power up status bit is set to 1. The Host shall read this status bit to identify

SDSC Card or

SDHC/SDXC

Card.