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NI sbRIO-9651 System on Module Carrier Board Design Guide
SD Signal Definitions
Table 1-12 describes the SD pins and signals on the sbRIO-9651 SOM connector.
Table 1-12.
SD Signal Definitions
Signal Name
Dedicated
SOM Pin #
Direction
*
I/O Standard
Description
SD_CLK
15
O
LVTTL
SD clock.
SD_CMD
31
I/O
LVTTL
SD command.
SD_D0
SD_D1
SD_D2
SD_D3
8
22
24
30
I/O
LVTTL
SD data bus.
SD_CD#
32
I
LVTTL
SD card detect.
Assert low when
card is present.
Can connect to a
mechanical switch in
the SD card socket.
SD_WP
40
I
LVTTL
SD write protect.
Assert high to enable
protection. Can
connect to a
mechanical switch in
the SD card socket.
SD_PWR_EN
38
O
LVTTL
Power enable for SD
card socket.
*
I/O direction is with respect to the sbRIO-9651 SOM.