NXP Semiconductors

UM12262

FRDM-IMX91 Board User Manual

2.8 SD card interface

The target processor has three ultra secured digital host controller (uSDHC) modules for SD/eMMC interface

support. The uSDHC2 interface of the i.MX 91 processor connects to the MicroSD card slot (P13) on the

FRDM-IMX91 board. This connector supports one 4-bit SD3.0 MicroSD card. To select it as the boot device of

the board, see Section 2.5.

2.9 eMMC memory

The eMMC memory (at the SOM board) is connected to the uSDHC1 interface of the i.MX 91 processor, which

can support eMMC 5.1 devices. It is the default boot device of the board. Table 12 describes the boot settings.

Table 14 describes the eMMC memory device that is supported by the uSDHC1 interface.

Part identifier Part number

Configuration

FBGA

Manufacturer

Memory size

U501

FEMDRM008G-58A39

64 Gb x1

TFBGA-153

FORESEE

8 GB

Table 14. Supported eMMC device

2.10 M.2 interface

The FRDM-IMX91 board supports the M.2/NGFF Key E mini card 75-pin connector, P8. The M.2 mini card

connector supports USB, SDIO, SAI, UART, I2C, and GPIO connection. By default, these signals are connected

with the onboard tri-radio MAYA-W476-00B module, however, to use this M.2 slot, the following resistors must

be reworked.

Resistors DNP

Resistors install

R2808, R2809, R2812, R2819, R2820, R2821

R2824, R2825, R2826, R2827, R2828, R2829

R3023, R3024, R2958, R3028

R2960, R2860

R2854, R2855

R2851, R2853

R3038, R2870, R2871

R3037, R2866, R2867

R2796, R2798, R2800, R2802

R2788, R2791, R2792, R2794

R2797, R2799, R2801, R2805

R2789, R2790, R2793, R2795

R2832, R2834, R2836, R2838

R2833, R2835, R2837, R2839

Table 15. Resistors rework for M.2 slot usage

The M.2 connector can be used for Wi-Fi / Bluetooth card, IEEE 802.15.4 Radio, or 3G / 4G cards.

Table 16 describes the pinout of the M.2 mini card connector (P8).

Pin number

M.2 mini card connector

pin

Connection details

2, 4, 72, 74

3V3_1, 3V3_2, 3V3_3,

3V3_4

Connected to VPCIe_3V3 power supply

6

LED1

Connected to M.2 Green LED, D613

8

I2S_SCK

Connected to SAI1_TXC processor pin if R2788 is populated

10

I2S_WS

Connected to SAI1_TXFS processor pin if R2791 is populated

12

I2S_SD_IN

Connected to SAI1_RXD processor pin if R2794 is populated

Table 16. M.2 mini card connector (P8) pinout

UM12262

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User manual

Rev. 3.0 — 22 April 2025

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