README

Overview

This example demonstrates how to use Non-Volatile Storage (NVS) through an interactive console interface. It provides a set of commands to read, write, and manage data in NVS.

Hardware Required

This example can run on any ESP32 family development board.

Configuration

The example can be configured through menuconfig:

1. Enable/disable command history storage (CONFIG_CONSOLE_STORE_HISTORY)
2. Configure UART parameters
3. Configure console prompt color settings

How to Use

Build and Flash

Build the project and flash it to the board, then run monitor tool to view serial output:

idf.py -p PORT flash monitor

(Replace PORT with the name of the serial port to use.)

Console Commands

The following commands are available:

1. NVS Operations:

   • nvs_namespace <namespace> - Set current namespace

     • Example: nvs_namespace storage

   • nvs_set <key> <type> -v <value> - Set a value in NVS

     • type can be: i8, u8, i16, u16 i32, u32 i64, u64, str, blob
     • Example: nvs_set counter i32 -v 42
     • Example: nvs_set name str -v "esp"
     • Example: nvs_set blob_val blob -v "657370" - To set a blob value, provide the hex representation of the data you want to store. For example, 65 (e), 73 (s), 70 (p).

   • nvs_get <key> - Get a value from NVS

     • Example: nvs_get counter

   • nvs_erase <key> - Erase a key from NVS

     • Example: nvs_erase counter

   • nvs_list <partition> [-n <namespace>] [-t <type>] - List stored key-value pairs stored in NVS. Use default partition name 'nvs' for listing the stored data.

     • Example: nvs_list nvs - This command lists all namespaces and their stored key-value pairs in the 'nvs' partition.
     • Example: nvs_list nvs -n storage -t i8

   • nvs_erase_namespace <namespace> - Erases specified namespace

     • Example: nvs_erase_namespace storage

2. System Commands:

   • help - List all commands
   • free - Get the current size of free heap memory
   • restart - Software reset of the chip
   • version - Get the chip info together with ESP-IDF version used in the application
   • heap - Get minimum size of free heap memory that was available during program execution

Example Output

...
NVS Console Example
-------------------
Type 'help' to get the list of commands.
Use UP/DOWN arrows to navigate through command history.
Press TAB when typing command name to auto-complete.
Press Ctrl+C to exit the console.

nvs> version
IDF Version:v5.5-dev-2627-g2cbfce97768-dirt
Chip info:
	model:ESP32
	cores:2
	feature:/802.11bgn/BLE/BT/External-Flash:2 MB
	revision number:0
nvs> free
298172
nvs> heap
min heap size: 298156
nvs> nvs_list nvs
namespace 'storage_1', key 'u8_key', type 'u8'
namespace 'storage_1', key 'i8_key', type 'i8'
namespace 'storage_1', key 'u16_key', type 'u16'
namespace 'storage_2', key 'u32_key', type 'u32'
namespace 'storage_2', key 'i32_key', type 'i32'
namespace 'storage_2', key 'str_key', type 'str'
nvs> nvs_namespace storage_1
I (85497) cmd_nvs: Namespace set to 'storage_1'
nvs> nvs_get i8_key i8
-128
nvs> nvs_set i8_key i8 -v -50
I (233297) cmd_nvs: Value stored under key 'i8_key'
nvs> nvs_get i8_key i8
-50
nvs>
...