# SD card

***Copyright © Quectel Wireless Solutions Co., Ltd. 2026. All rights reserved.***

---

An SD card (Secure Digital Card) is a widely used portable storage medium featuring small size, large capacity, low power consumption, and ease of use. It is commonly used in mobile phones, cameras, embedded devices, and single-board computers to store system files, applications, and user data. It is one of the most prevalent storage solutions in modern mobile and embedded systems.

The Quectel Pi H1 single-board computer includes one push‑type SD card slot compliant with the SD 3.0 specification.

# Hardware interface

Insert the SD card into the SD card slot of the Quectel Pi H1 single-board computer.

```{image} images/image_Z5lhbSXj8oto7bxA91nc6Dv3nLe.webp
:width: 604px
:height: 321px
```

# Function usage

## System recognition

After inserting the SD card, use the following command to check whether the system has detected the device:

```bash
lsblk
```

Example output：

```plaintext
NAME        MAJ:MIN RM   SIZE RO TYPE MOUNTPOINTS
sda           8:0    0 116.1G  0 disk
|-sda1        8:1    0   512M  0 part /efi
|-sda2        8:2    0    30M  0 part /var/persist
`-sda3        8:3    0 115.6G  0 part /
sdb           8:16   0     8M  0 disk
|-sdb1        8:17   0   3.5M  0 part
|-sdb2        8:18   0   512K  0 part
`-sdb3        8:19   0   3.5M  0 part
sdc           8:32   0     8M  0 disk
|-sdc1        8:33   0   3.5M  0 part
|-sdc2        8:34   0   512K  0 part
`-sdc3        8:35   0   3.5M  0 part
sdd           8:48   0    32M  0 disk
|-sdd1        8:49   0   104K  0 part
|-sdd2        8:50   0   128K  0 part
|-sdd3        8:51   0     1M  0 part
|-sdd4        8:52   0     1M  0 part
`-sdd5        8:53   0     1M  0 part
sde           8:64   0     3G  0 disk
|-sde1        8:65   0   512K  0 part
|-sde2        8:66   0    64M  0 part
|-sde3        8:67   0   256K  0 part
|-sde4        8:68   0     2M  0 part
|-sde5        8:69   0     5M  0 part
|-sde6        8:70   0     4M  0 part
|-sde7        8:71   0     8M  0 part
|-sde8        8:72   0     4M  0 part
|-sde9        8:73   0    32M  0 part
|-sde10       8:74   0   128K  0 part
|-sde11       8:75   0    80K  0 part
|-sde12       8:76   0     2M  0 part
|-sde13       8:77   0     2M  0 part
|-sde14       8:78   0   128K  0 part
|-sde15       8:79   0    32K  0 part
|-sde16     259:0    0     1M  0 part
|-sde17     259:1    0   256K  0 part
|-sde18     259:2    0   512K  0 part
|-sde19     259:3    0   256K  0 part
|-sde20     259:4    0    64M  0 part
|-sde21     259:5    0     2M  0 part
|-sde22     259:6    0     5M  0 part
|-sde23     259:7    0     4M  0 part
|-sde24     259:8    0     8M  0 part
|-sde25     259:9    0     4M  0 part
|-sde26     259:10   0    32M  0 part
|-sde27     259:11   0   128K  0 part
|-sde28     259:12   0    80K  0 part
|-sde29     259:13   0     2M  0 part
|-sde30     259:14   0     2M  0 part
|-sde31     259:15   0   128K  0 part
|-sde32     259:16   0    32K  0 part
|-sde33     259:17   0     1M  0 part
|-sde34     259:18   0   256K  0 part
|-sde35     259:19   0     4K  0 part
|-sde36     259:20   0     4K  0 part
|-sde37     259:21   0     4K  0 part
|-sde38     259:22   0    16M  0 part
|-sde39     259:23   0    30M  0 part
|-sde40     259:24   0     1M  0 part
|-sde41     259:25   0  32.6M  0 part
|-sde42     259:26   0     4K  0 part
|-sde43     259:27   0     4K  0 part
|-sde44     259:28   0     1M  0 part
|-sde45     259:29   0     8M  0 part
|-sde46     259:30   0    40M  0 part
|-sde47     259:31   0   512M  0 part
|-sde48     259:32   0    28K  0 part
|-sde49     259:33   0   512K  0 part
|-sde50     259:34   0     1M  0 part
`-sde51     259:35   0  32.6M  0 part
sdf           8:80   0    32M  0 disk
|-sdf1        8:81   0     3M  0 part
|-sdf2        8:82   0     3M  0 part
|-sdf3        8:83   0     3M  0 part
`-sdf4        8:84   0   128K  0 part
mmcblk1     179:0    0  29.5G  0 disk
`-mmcblk1p1 179:1    0  29.5G  0 part /media/sdcard
zram0       253:0    0   3.8G  0 disk [SWAP]
```

**Key output section:**

```plaintext
mmcblk1     179:0    0  29.5G  0 disk
`-mmcblk1p1 179:1    0  29.5G  0 part /media/sdcard
```

> **Note**：If the SD card is not detected, check:
> 1. Whether the SD card is inserted correctly.
> 2. Whether the SD card is formatted.
> 3. Whether the system supports this SD card type/specification.

## Mounting and unmounting

### Automatic mounting

When the SD card is automatically mounted, you will see the output as exemplified below:

```plaintext
mmcblk1     179:0    0  29.5G  0 disk
`-mmcblk1p1 179:1    0  29.5G  0 part /media/sdcard
```

The above example indicates the SD card is automatically mounted at `/media/sdcard`.

Check the mount result:

`ls /media/sdcard`

### Manual mounting

If you need to mount the SD card manually to a specified directory, follow the steps below:

1. Create a mount point.

```bash
sudo mkdir -p /mnt/sdcard
```

2. Mount the SD card.

```bash
sudo mount /dev/mmcblk1p1 /mnt/sdcard
```

3. Verify the mount result.

```bash
ls /mnt/sdcard
```

### Safe unmounting

Always unmount the SD card before removal to avoid data corruption:

```bash
sudo umount /mnt/sdcard
```

## File operations and permissions

Regular users may encounter permission issues when accessing SD card files. You can change the owner of the mount directory using the following commands:

```bash
sudo chown <username> /mnt/sdcard
sudo chmod 755 /mnt/sdcard
```

Replace ``<username>`` with the current logged‑in username.  
After this, you will have normal read/write access to `/mnt/sdcard`.