docs(esp32h21): Add documentation for ESP32-H21

Author: jedi7

.github/copilot-instructions.md

@@ -10,7 +10,7 @@ This document provides essential information for coding agents working on the es
 - `espsecure.py` - Security-related operations (signing, encryption)
 - `esp_rfc2217_server.py` - RFC2217 serial-over-TCP server
 
-**Project type:** Python 3.10+ package with console entry points, using setuptools build system and Click/rich_click for CLI interfaces. Supports ESP32, ESP32-S2, ESP32-S3, ESP32-C2, ESP32-C3, ESP32-C5, ESP32-C6, ESP32-H2, ESP32-P4, ESP8266, and other Espressif chips.
+**Project type:** Python 3.10+ package with console entry points, using setuptools build system and Click/rich_click for CLI interfaces. Supports ESP32, ESP32-S2, ESP32-S3, ESP32-C2, ESP32-C3, ESP32-C5, ESP32-C6, ESP32-H2, ESP32-H21, ESP32-P4, ESP8266, and other Espressif chips.
 
 **Repository size:** ~200 files, primarily Python code with some binary stub flasher files and YAML configuration files.
 
@@ -35,7 +35,7 @@ This document provides essential information for coding agents working on the es
 3. **Verify installation works:**
    ```bash
    esptool.py --help
-   espefuse.py --help  
+   espefuse.py --help
    espsecure.py --help
    esp_rfc2217_server.py --help
    ```
@@ -163,7 +163,7 @@ esptool recognizes these environment variables for default behavior:
 - **`ESPTOOL_PORT`** - Default serial port
 - **`ESPTOOL_BAUD`** - Default baud rate
 - **`ESPTOOL_FF`** - Default flash frequency
-- **`ESPTOOL_FM`** - Default flash mode  
+- **`ESPTOOL_FM`** - Default flash mode
 - **`ESPTOOL_FS`** - Default flash size
 - **`ESPTOOL_BEFORE`** - Default reset mode before operation
 - **`ESPTOOL_AFTER`** - Default reset mode after operation

.gitlab-ci.yml

@@ -545,7 +545,7 @@ build_docs:
   script:
     - pip install ".[docs]" --prefer-binary  # esptool is needed for the automatic API documentation generation
     - cd docs
-    - build-docs -l en -t {esp8266,esp32,esp32s2,esp32c3,esp32s3,esp32c2,esp32c6,esp32h2,esp32p4,esp32c5,esp32c61}
+    - build-docs -l en -t {esp8266,esp32,esp32s2,esp32c3,esp32s3,esp32c2,esp32c6,esp32h2,esp32p4,esp32c5,esp32c61,esp32h21}
 
 .deploy_docs_template:
   stage: deploy_docs

docs/_static/esptool_versions.js

@@ -3,20 +3,21 @@ var DOCUMENTATION_VERSIONS = {
                 supported_targets: [ "esp32" ]
               },
     VERSIONS: [
-       { name: "latest", old: false, pre_release: false, supported_targets: [ "esp8266", "esp32", "esp32s2", "esp32s3", "esp32c3", "esp32c2", "esp32c6", "esp32p4", "esp32h2", "esp32c5", "esp32c61" ] },
-       { name: "release-v4", old: false, pre_release: false, supported_targets: [ "esp8266", "esp32", "esp32s2", "esp32s3", "esp32c3", "esp32c2", "esp32c6", "esp32p4", "esp32h2", "esp32c5", "esp32c61" ] },
+       { name: "latest", old: false, pre_release: false, supported_targets: [ "esp8266", "esp32", "esp32s2", "esp32s3", "esp32c3", "esp32c2", "esp32c6", "esp32p4", "esp32h2", "esp32c5", "esp32c61", "esp32h21" ] },
+       { name: "release-v4", old: false, pre_release: false, supported_targets: [ "esp8266", "esp32", "esp32s2", "esp32s3", "esp32c3", "esp32c2", "esp32c6", "esp32p4", "esp32h2", "esp32c5", "esp32c61", "esp32h21" ] },
     ],
     IDF_TARGETS: [
-       { text: "ESP8266", value: "esp8266" },
        { text: "ESP32", value: "esp32" },
-       { text: "ESP32-S2", value: "esp32s2" },
-       { text: "ESP32-S3", value: "esp32s3" },
-       { text: "ESP32-C3", value: "esp32c3" },
        { text: "ESP32-C2", value: "esp32c2" },
+       { text: "ESP32-C3", value: "esp32c3" },
+       { text: "ESP32-C5", value: "esp32c5" },
        { text: "ESP32-C6", value: "esp32c6" },
+       { text: "ESP32-C61", value: "esp32c61" },
        { text: "ESP32-H2", value: "esp32h2" },
+       { text: "ESP32-H21", value: "esp32h21" },
        { text: "ESP32-P4", value: "esp32p4" },
-       { text: "ESP32-C5", value: "esp32c5" },
-       { text: "ESP32-C61", value: "esp32c61" },
+       { text: "ESP32-S2", value: "esp32s2" },
+       { text: "ESP32-S3", value: "esp32s3" },
+       { text: "ESP8266", value: "esp8266" },
     ]
 };

docs/conf_common.py

@@ -13,6 +13,7 @@
     "esp32p4",
     "esp32c5",
     "esp32c61",
+    "esp32h21",
 ]
 
 # link roles config
@@ -53,6 +54,7 @@
     "esp32p4": ESP32_DOCS,
     "esp32c5": ESP32_DOCS,
     "esp32c61": ESP32_DOCS,
+    "esp32h21": ESP32_DOCS,
 }
 
 # Extra options required by sphinx_idf_theme

docs/en/advanced-topics/boot-mode-selection.rst

@@ -1,6 +1,6 @@
-{IDF_TARGET_STRAP_BOOT_GPIO:default="GPIO9", esp8266="GPIO0", esp32="GPIO0", esp32s2="GPIO0", esp32s3="GPIO0", esp32p4="GPIO35", esp32c5="GPIO28"}
+{IDF_TARGET_STRAP_BOOT_GPIO:default="GPIO9", esp8266="GPIO0", esp32="GPIO0", esp32s2="GPIO0", esp32s3="GPIO0", esp32p4="GPIO35", esp32c5="GPIO28", esp32h21="GPIO14"}
 
-{IDF_TARGET_STRAP_BOOT_2_GPIO:default="GPIO8", esp32="GPIO2", esp32s2="GPIO46", esp32s3="GPIO46", esp32p4="GPIO36", esp32c5="GPIO27"}
+{IDF_TARGET_STRAP_BOOT_2_GPIO:default="GPIO8", esp32="GPIO2", esp32s2="GPIO46", esp32s3="GPIO46", esp32p4="GPIO36", esp32c5="GPIO27", esp32h21="GPIO13"}
 
 {IDF_TARGET_BOOTLOADER_OFFSET:default="0x0", esp32="0x1000", esp32s2="0x1000", esp32p4="0x2000", esp32c5="0x2000"}
 
@@ -87,7 +87,7 @@ This guide explains how to select the boot mode correctly and describes the boot
 
       {IDF_TARGET_STRAP_BOOT_2_GPIO} must also be either left unconnected/floating, or driven Low, in order to enter the serial bootloader.
 
-   .. only:: esp32c3 or esp32c2 or esp32h2 or esp32c6 or esp32p4 or esp32c5 or esp32c61
+   .. only:: esp32c3 or esp32c2 or esp32h2 or esp32c6 or esp32p4 or esp32c5 or esp32c61 or esp32h21
 
       {IDF_TARGET_STRAP_BOOT_2_GPIO} must also be driven High, in order to enter the serial bootloader reliably. The strapping combination of {IDF_TARGET_STRAP_BOOT_2_GPIO} = 0 and {IDF_TARGET_STRAP_BOOT_GPIO} = 0 is invalid and will trigger unexpected behavior.
 

docs/en/advanced-topics/firmware-image-format.rst

@@ -1,10 +1,10 @@
-{IDF_TARGET_FLASH_FREQ_F:default="80", esp32c2="60", esp32h2="48"}
+{IDF_TARGET_FLASH_FREQ_F:default="80", esp32c2="60", esp32h2="48", esp32h21="48"}
 
-{IDF_TARGET_FLASH_FREQ_0:default="40", esp32c2="30", esp32h2="24"}
+{IDF_TARGET_FLASH_FREQ_0:default="40", esp32c2="30", esp32h2="24", esp32h21="24"}
 
-{IDF_TARGET_FLASH_FREQ_1:default="26", esp32c2="20", esp32h2="16"}
+{IDF_TARGET_FLASH_FREQ_1:default="26", esp32c2="20", esp32h2="16", esp32h21="16"}
 
-{IDF_TARGET_FLASH_FREQ_2:default="20", esp32c2="15", esp32h2="12"}
+{IDF_TARGET_FLASH_FREQ_2:default="20", esp32c2="15", esp32h2="12", esp32h21="12"}
 
 {IDF_TARGET_BOOTLOADER_OFFSET:default="0x0", esp32="0x1000", esp32s2="0x1000", esp32p4="0x2000", esp32c5="0x2000"}
 
@@ -103,7 +103,7 @@ The image header is 8 bytes long:
         Flash frequency with value ``0`` can mean either 80MHz or 40MHz based on MSPI clock source mode.
 
 
-.. only:: esp32c5 or esp32c61
+.. only:: esp32c5 or esp32c61 or esp32h21
 
     +--------+------------------------------------------------------------------------------------------------+
     | Byte   | Description                                                                                    |
@@ -121,7 +121,7 @@ The image header is 8 bytes long:
     | 4-7    | Entry point address                                                                            |
     +--------+------------------------------------------------------------------------------------------------+
 
-.. only:: not (esp8266 or esp32c6 or esp32s3 or esp32s2 or esp32p4 or esp32c5 or esp32c61)
+.. only:: not (esp8266 or esp32c6 or esp32s3 or esp32s2 or esp32p4 or esp32c5 or esp32c61 or esp32h21)
 
     +--------+------------------------------------------------------------------------------------------------+
     | Byte   | Description                                                                                    |