Product manual

Secure Digital (SD) Card Protocol Description

Current State

idle ready ident stby tran data rcv prg dis ina

CMD32 - - - - tran - - - - -

CMD33 - - - - tran - - - - -

CMD38 - - - - prg - - - - -

Class 7

CMD42 This is an SDA optional command supported by the SanDisk Industrial Grade SD Card.

Class 8

CMD55 idle - - stby tran data rcv prg dis -

CMD56; RD/WR = 0 - - - - rcv - - - - -

CMD56; RD/WR = 1 - - - - data - - - - -

ACMD6 - - - - tran - - - - -

ACMD13 - - - - tran - - - - -

ACMD22 - - - - tran - - - - -

ACMD23 - - - - tran - - - - -

ACMD18,25,26,38,

43,44,45,46,47,48,49

Refer to SD Card Security Specification for an explanation of the SD Security Features. The

SanDisk Industrial Grade SD Card supports all the security related commands as explained in the

specification.

ACMD41, card V

range

compatible

ready - - - - - - - - -

ACMD41, card is busy idle - - - - - - - - -

ACMD41, card V

range not

compatible

ina - - - - - - - - -

ACMD42 - - - - tran - - - - -

ACMD51 - - - - data - - - - -

class 9- 11

CMD41; CMD43...CMD54,

CMD57-CMD59

Reserved

CMD60...CMD63 Reserved for manufacturer

4.10. Responses

All responses are sent via the CMD line. The response transmission always starts with the MSB. The response

length depends on the response type.

A response always starts with a start bit (always ‘0’), followed by the bit indicating the direction of transmission

(card = ‘0’). A value denoted by ‘x’ in the tables below indicates a variable entry. All responses except for the type

R3 (see below) are protected by a CRC. Every response is terminated by the end bit (always ‘1’).

There are four types of responses that are supported in the SanDisk Industrial Grade SD Card. Their formats are

defined as follows: