Connect a SD/SDIO/MMC-Card-Socket to a Trizeps

1 Schematic
2 Signals

Applies to: Trizeps IV(M), Trizeps IV WL, Trizeps V, Trizeps VI.
See also: SD/SDIO/MMC.

Schematic

Typical connection of a SD-Card Slot

This is the typical SD-Card-Slot schematic used on almost all of our baseboards: ConXS, uConXS, iPAN7.

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uSD-Card Slot without Card- and Write- Protect

This is the minimum configuration for a SD-Card-Slot. Check with Seco wether leaving the SDIO_CARD_DETECT-signal floating is supported by the BSP. Otherwise you need to connect SDIO_CARD_DETECT with a pull-up to 3.3V. The big disadvantage is, that you can't add or remove cards while the OS

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SD-Card Slot connection when long signal traces used

This is a schematic for a SD-Card-Slot which is far away from the SODIMM-socket. i.e. the i-PAN7 Connector Board.

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Signals

Signal-Name	SODIMM-Pin	Remark

Signal-Name	SODIMM-Pin	Remark
SDIO_CMD	190	add pull-up(10K..100K). This must have a smaller pull-up than SDIO_DATx-signals do.
SDIO_CLK	47
SDIO_DAT0	192	add pull-up(10K..100K)
SDIO_DAT1	81	add pull-up(10K..100K)
SDIO_DAT2	85	add pull-up(10K..100K)
SDIO_DAT3	51	add pull-up(10K..100K)
SDIO_CARD_DETECT	59	Connect in a way, that pin is high(3.3V) when card is inserted and low (0V) when card is removed. Note that other SD-card-sockets may have different ways how to handle their COMM, CD and WP pins.
SDIO_WRITE_PROTECT	(any gpio)

A 100nF capacitor must be placed near the SDIO-card-socket pins VDD, VSS1, VSS2.