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EEPROM Shell

Overview

The EEPROM shell provides an eeprom command with a set of subcommands for the shell module. It allows testing and exploring the EEPROM driver API through an interactive interface without having to write a dedicated application. The EEPROM shell can also be enabled in existing applications to aid in interactive debugging of EEPROM issues.

In order to enable the EEPROM shell, the following Kconfig options must be enabled:

For example, building the Hello World sample for the Native simulator - native_sim with the EEPROM shell:

# From the root of the zephyr repository
west build -b native_sim samples/hello_world -- -DCONFIG_SHELL=y -DCONFIG_EEPROM=y -DCONFIG_EEPROM_SHELL=y

See the shell documentation for general instructions on how to connect and interact with the shell. The EEPROM shell comes with built-in help (unless CONFIG_SHELL_HELP is disabled). The built-in help messages can be printed by passing -h or --help to the eeprom command or any of its subcommands. All subcommands also support tab-completion of their arguments.

Tip

All of the EEPROM shell subcommands take the name of an EEPROM peripheral as their first argument, which also supports tab-completion. A list of all devices available can be obtained using the device list shell command when CONFIG_DEVICE_SHELL is enabled. The examples below all use the device name eeprom@0.

EEPROM Size

The size of an EEPROM can be inspected using the eeprom size subcommand as shown below:

uart:~$ eeprom size eeprom@0
32768 bytes

Writing Data

Data can be written to an EEPROM using the eeprom write subcommand. This subcommand takes at least three arguments; the EEPROM device name, the offset to start writing to, and at least one data byte. In the following example, the hexadecimal sequence of bytes 0x0d 0x0e 0x0a 0x0d 0x0b 0x0e 0x0e 0x0f is written to offset 0x0:

uart:~$ eeprom write eeprom@0 0x0 0x0d 0x0e 0x0a 0x0d 0x0b 0x0e 0x0e 0x0f
Writing 8 bytes to EEPROM...
Verifying...
Verify OK

It is also possible to fill a portion of the EEPROM with the same pattern using the eeprom fill subcommand. In the following example, the pattern 0xaa is written to 16 bytes starting at offset 0x8:

uart:~$ eeprom fill eeprom@0 0x8 16 0xaa
Writing 16 bytes of 0xaa to EEPROM...
Verifying...
Verify OK

Reading Data

Data can be read from an EEPROM using the eeprom read subcommand. This subcommand takes three arguments; the EEPROM device name, the offset to start reading from, and the number of bytes to read:

uart:~$ eeprom read eeprom@0 0x0 8
Reading 8 bytes from EEPROM, offset 0...
00000000: 0d 0e 0a 0d 0b 0e 0e 0f                          |........         |