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MSC SM2S-IMX8M User Manual
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4.11 SDIO
The SDIO interface on the SMARC
™ connector supports:
1-bit / 4-bit for SD/SDIO mode (standard up to version 3.0)
1-bit / 4-bit for MMC mode (standard up to version 5.1)
SD/SDIO 1.8 V (UHS-I) or 3.3 V operation with auto detection
Normal-speed, high-speed, SDR50 and SDR104 mode
Table 4-11: SDIO Signal Description
Signal
Pin
Type
Signal Level
Pin on
i.MX8M
Pin name on
i.MX8M
Power
Tolerance
PU/PD
Description
SDIO_D0
I/O
3.3V / 1V8 CMOS N22
SD2_DATA0
3.3V / 1.8V
PU 10k 3.3V / 1.8V
SDIO Controller Data
SDIO_D1
I/O
3.3V / 1V8 CMOS N21
SD2_DATA1
3.3V / 1.8V
PU 10k 3.3V / 1.8V
SDIO Controller Data
SDIO_D2
I/O
3.3V / 1V8 CMOS P22
SD2_DATA2
3.3V / 1.8V
PU 10k 3.3V / 1.8V
SDIO Controller Data
SDIO_D3
I/O
3.3V / 1V8 CMOS P21
SD2_DATA3
3.3V / 1.8V
PU 10k 3.3V / 1.8V
SDIO Controller Data
SDIO_CMD
I/O
3.3V / 1V8 CMOS M22
SD2_CMD
3.3V / 1.8V
PU 10k 3.3V / 1.8V
SDIO Controller Command
SDIO_CK
O
3.3V / 1V8 CMOS L22
SD2_CLK
3.3V / 1.8V
PU 10k 3.3V / 1.8V
SDIO Controller Clock
SDIO_PWR_EN O PP
3.3V CMOS
K1
SAI1_RXC
3.3V / 1.8V
PD 1k
SDIO Controller Power enable
(CPU GPIO4_IO01)
SDIO_CD#
I
3.3V / 1V8 CMOS L21
SD2_CD_B
3.3V / 1.8V
PU 10k 3.3V / 1.8V
SDIO Controller Card Detect
SDIO_WP
I
3.3V / 1V8 CMOS M21
SD2_WP
3.3V / 1.8V
PU 10k 3.3V / 1.8V
SDIO Controller Write Protect