Rsi Commands And Responses - Analog Devices ADSP-BF506F Hardware Reference Manual

RSI Commands and Responses

The RSI sends commands to and receives responses from the card via the
signal. The command to be sent to the card is issued by writing to
RSI_CMD
the
RSI_COMMAND
(RSI_COMMAND)" on page
field that contains the command index to be sent to the card pro-
CMD_IDX
viding support for a total of 64 commands, 0 (CMD0) to 63 (CMD63).
Some commands require an argument to be sent along with the command,
such as an address for a read transaction. An argument is always sent with
the command and it is the responsibility of the card to either ignore or use
the argument field based on the command that is received. The argument
sent with the command is provided via the
(see "RSI Argument Register (RSI_ARGUMENT)" on page
All command transfers are protected by a 7-bit cyclic redundancy check
(CRC) code, more commonly referred to as a CRC7 checksum. This
allows for transmission errors to be detected and the command to be
re-issued to the card in the event of an error. All commands sent to the
card are composed of 48-bits as shown in
Table 21-4. RSI Command Format
Bit Position
47
46
45:40
39:8
7:1
0
The
RSI_COMMAND
required command, also provides configuration information on whether a
response is to be expected back from the card and the type of response.
ADSP-BF50x Blackfin Processor Hardware Reference
register (see "RSI Command Register
21-57). This register contains a 6-bit
Width Value
1 0
1 1
6 -
32 -
7 -
1 1
register, as well as providing a means for issuing the
Removable Storage Interface
RSI_ARGUMENT
Table 21-4.
Description
Start bit
Transmitter bit
Command index
Argument
CRC7 checksum
End bit
register
21-57).
21-15