diff --git a/builder/frameworks/espidf.py b/builder/frameworks/espidf.py
index e53be61..781f547 100644
--- a/builder/frameworks/espidf.py
+++ b/builder/frameworks/espidf.py
@@ -35,6 +35,11 @@ platform = env.PioPlatform()
 env.SConscript("_bare.py", exports="env")
 env.SConscript("_embedtxt_files.py", exports="env")
 
+ulp_lib = None
+ulp_dir = join(env.subst("$PROJECT_DIR"), "ulp")
+if isdir(ulp_dir) and listdir(ulp_dir):
+    ulp_lib = env.SConscript("ulp.py", exports="env")
+
 FRAMEWORK_DIR = platform.get_package_dir("framework-espidf")
 assert FRAMEWORK_DIR and isdir(FRAMEWORK_DIR)
 
@@ -56,6 +61,12 @@ def get_toolchain_version():
         platform.get_package_version("toolchain-xtensa32"))
 
 
+def is_ulp_enabled(sdk_params):
+    ulp_memory = int(sdk_params.get("CONFIG_ULP_COPROC_RESERVE_MEM", 0))
+    ulp_enabled = int(sdk_params.get("CONFIG_ULP_COPROC_ENABLED", 0))
+    return ulp_memory > 0 and ulp_enabled != 0
+
+
 def parse_mk(path):
     result = {}
     variable = None
@@ -608,6 +619,20 @@ env.Depends("$BUILD_DIR/$PROGNAME$PROGSUFFIX", env.ElfToBin(
 
 libs = []
 
+if ulp_lib:
+    if not is_ulp_enabled(sdk_params):
+        print("Warning! ULP is not properly configured."
+              "Add next configuration lines to your sdkconfig.h:")
+        print ("    #define CONFIG_ULP_COPROC_ENABLED 1")
+        print ("    #define CONFIG_ULP_COPROC_RESERVE_MEM 1024")
+
+    libs.append(ulp_lib)
+    env.Append(
+        CPPPATH=[join("$BUILD_DIR", "ulp_app")],
+        LIBPATH=[join("$BUILD_DIR", "ulp_app")],
+        LINKFLAGS=["-T", "ulp_main.ld"]
+    )
+
 ignore_dirs = (
     "bootloader",
     "esptool_py",
diff --git a/builder/frameworks/ulp.py b/builder/frameworks/ulp.py
new file mode 100644
index 0000000..3d261ee
--- /dev/null
+++ b/builder/frameworks/ulp.py
@@ -0,0 +1,171 @@
+# Copyright 2019-present PlatformIO <contact@platformio.org>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from os import remove
+from os.path import exists, join
+
+from shutil import copyfile
+
+from SCons.Script import Builder, Import, Return
+
+Import("env")
+
+ulp_env = env.Clone()
+
+platform = ulp_env.PioPlatform()
+FRAMEWORK_DIR = platform.get_package_dir("framework-espidf")
+ULP_TOOLCHAIN_DIR = platform.get_package_dir("toolchain-esp32ulp")
+ULP_BUILD_DIR = join("$BUILD_DIR", "ulp_app")
+
+# ULP toolchain binaries should be in PATH
+ulp_env.PrependENVPath("PATH", join(ULP_TOOLCHAIN_DIR, "bin"))
+
+
+def bin_converter(target, source, env):
+    # A workaround that helps avoid changing working directory
+    # in order to generate symbols that are irrespective of path
+    temp_source = join(env.subst("$PROJECT_DIR"), source[0].name)
+    copyfile(source[0].get_path(), temp_source)
+
+    command = " ".join([
+        "xtensa-esp32-elf-objcopy", "--input-target",
+        "binary", "--output-target",
+        "elf32-xtensa-le", "--binary-architecture",
+        "xtensa", "--rename-section",
+        ".data=.rodata.embedded",
+        source[0].name, target[0].get_path()
+    ])
+
+    ulp_env.Execute(command)
+
+    if exists(temp_source):
+        remove(temp_source)
+
+    return None
+
+
+ulp_env.Append(
+    CPPPATH=["$PROJECTSRC_DIR"],
+
+    BUILDERS=dict(
+        BuildElf=Builder(
+            action=ulp_env.VerboseAction(" ".join([
+                "esp32ulp-elf-ld",
+                "-o", "$TARGET",
+                "-A", "elf32-esp32ulp",
+                "-L", ULP_BUILD_DIR,
+                "-T", "ulp_main.common.ld",
+                "$SOURCES"
+            ]), "Linking $TARGET"),
+            suffix=".elf"
+        ),
+        UlpElfToBin=Builder(
+            action=ulp_env.VerboseAction(" ".join([
+                "esp32ulp-elf-objcopy",
+                "-O", "binary",
+                "$SOURCE", "$TARGET"
+            ]), "Building $TARGET"),
+            suffix=".bin"
+        ),
+        ConvertBin=Builder(
+            action=bin_converter,
+            suffix=".bin.bin.o"
+        ),
+        PreprocAs=Builder(
+            action=ulp_env.VerboseAction(" ".join([
+                "xtensa-esp32-elf-gcc",
+                "-DESP_PLATFORM", "-MMD", "-MP", "-DGCC_NOT_5_2_0=0",
+                "-DWITH_POSIX", "-DHAVE_CONFIG_H",
+                "-MT", "${TARGET}.o",
+                "-DMBEDTLS_CONFIG_FILE=\"mbedtls/esp_config.h\"",
+                "-I %s" % join(
+                    FRAMEWORK_DIR, "components", "soc", "esp32", "include"),
+                "-E", "-P", "-xc",
+                "-o", "$TARGET", "-D__ASSEMBLER__", "$SOURCE"
+            ]), "Preprocessing $TARGET"),
+            single_source=True,
+            suffix=".ulp.pS"
+        ),
+        AsToObj=Builder(
+            action=ulp_env.VerboseAction(" ".join([
+                "esp32ulp-elf-as",
+                "-o", "$TARGET", "$SOURCE"
+            ]), "Compiling $TARGET"),
+            single_source=True,
+            suffix=".o"
+        )
+    )
+)
+
+
+def preprocess_ld_script():
+    arguments = ("-DESP_PLATFORM", "-MMD", "-MP", "-DGCC_NOT_5_2_0=0",
+                 "-DWITH_POSIX", "-D__ASSEMBLER__",
+                 '-DMBEDTLS_CONFIG_FILE="mbedtls/esp_config.h"',
+                 "-DHAVE_CONFIG_H", "-MT", "$TARGET", "-E", "-P", "-xc", "-o",
+                 "$TARGET", "-I $PROJECTSRC_DIR", "$SOURCE")
+
+    return ulp_env.Command(
+        join(ULP_BUILD_DIR, "ulp_main.common.ld"),
+        join(FRAMEWORK_DIR, "components", "ulp", "ld", "esp32.ulp.ld"),
+        ulp_env.VerboseAction('xtensa-esp32-elf-gcc %s' % " ".join(arguments),
+                              "Preprocessing linker script $TARGET"))
+
+
+def collect_src_files(src_path):
+    return ulp_env.CollectBuildFiles(ULP_BUILD_DIR, src_path)
+
+
+def generate_global_symbols(elf_file):
+    return ulp_env.Command(
+        join(ULP_BUILD_DIR, "ulp_main.sym"), elf_file,
+        ulp_env.VerboseAction(
+            "esp32ulp-elf-nm -g -f posix $SOURCE > $TARGET",
+            "Generating global symbols $TARGET"))
+
+
+def generate_export_files(symbol_file):
+    # generates ld script and header file
+    gen_script = join(FRAMEWORK_DIR, "components", "ulp", "esp32ulp_mapgen.py")
+    build_suffix = join(ULP_BUILD_DIR, "ulp_main")
+    return ulp_env.Command(
+        [join(ULP_BUILD_DIR, "ulp_main.ld"),
+         join(ULP_BUILD_DIR, "ulp_main.h")], symbol_file,
+        ulp_env.VerboseAction(
+            '"$PYTHONEXE" "%s" -s $SOURCE -o %s' % (gen_script, build_suffix),
+            "Exporting ULP linker and header files"))
+
+
+def create_static_lib(bin_file):
+    return ulp_env.StaticLibrary(join(ULP_BUILD_DIR, "ulp_main"), [bin_file])
+
+
+ulp_src_files = collect_src_files(
+    join(ulp_env.subst("$PROJECT_DIR"), "ulp"))
+objects = ulp_env.AsToObj(ulp_env.PreprocAs(ulp_src_files))
+ulp_elf = ulp_env.BuildElf(join(ULP_BUILD_DIR, "ulp_main"), objects)
+raw_ulp_binary = ulp_env.UlpElfToBin(ulp_elf)
+ulp_bin = ulp_env.ConvertBin(raw_ulp_binary)
+global_symbols = generate_global_symbols(ulp_elf)
+export_files = generate_export_files(global_symbols)
+
+ulp_lib = create_static_lib(ulp_bin)
+
+ulp_env.Depends(ulp_lib, export_files)
+ulp_env.Depends(ulp_elf, preprocess_ld_script())
+
+# ULP sources must be built before the files in "src" folder
+ulp_env.Requires(join("$BUILD_DIR", "${PROGNAME}.elf"), ulp_lib)
+
+Return("ulp_lib")
diff --git a/examples/espidf-ulp-adc/.gitignore b/examples/espidf-ulp-adc/.gitignore
new file mode 100644
index 0000000..6c69f4c
--- /dev/null
+++ b/examples/espidf-ulp-adc/.gitignore
@@ -0,0 +1,2 @@
+.pioenvs
+.piolibdeps
diff --git a/examples/espidf-ulp-adc/.travis.yml b/examples/espidf-ulp-adc/.travis.yml
new file mode 100644
index 0000000..7c486f1
--- /dev/null
+++ b/examples/espidf-ulp-adc/.travis.yml
@@ -0,0 +1,67 @@
+# Continuous Integration (CI) is the practice, in software
+# engineering, of merging all developer working copies with a shared mainline
+# several times a day < https://docs.platformio.org/page/ci/index.html >
+#
+# Documentation:
+#
+# * Travis CI Embedded Builds with PlatformIO
+#   < https://docs.travis-ci.com/user/integration/platformio/ >
+#
+# * PlatformIO integration with Travis CI
+#   < https://docs.platformio.org/page/ci/travis.html >
+#
+# * User Guide for `platformio ci` command
+#   < https://docs.platformio.org/page/userguide/cmd_ci.html >
+#
+#
+# Please choose one of the following templates (proposed below) and uncomment
+# it (remove "# " before each line) or use own configuration according to the
+# Travis CI documentation (see above).
+#
+
+
+#
+# Template #1: General project. Test it using existing `platformio.ini`.
+#
+
+# language: python
+# python:
+#     - "2.7"
+#
+# sudo: false
+# cache:
+#     directories:
+#         - "~/.platformio"
+#
+# install:
+#     - pip install -U platformio
+#     - platformio update
+#
+# script:
+#     - platformio run
+
+
+#
+# Template #2: The project is intended to be used as a library with examples.
+#
+
+# language: python
+# python:
+#     - "2.7"
+#
+# sudo: false
+# cache:
+#     directories:
+#         - "~/.platformio"
+#
+# env:
+#     - PLATFORMIO_CI_SRC=path/to/test/file.c
+#     - PLATFORMIO_CI_SRC=examples/file.ino
+#     - PLATFORMIO_CI_SRC=path/to/test/directory
+#
+# install:
+#     - pip install -U platformio
+#     - platformio update
+#
+# script:
+#     - platformio ci --lib="." --board=ID_1 --board=ID_2 --board=ID_N
diff --git a/examples/espidf-ulp-adc/README.rst b/examples/espidf-ulp-adc/README.rst
new file mode 100644
index 0000000..0a284cb
--- /dev/null
+++ b/examples/espidf-ulp-adc/README.rst
@@ -0,0 +1,38 @@
+..  Copyright 2014-present PlatformIO <contact@platformio.org>
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+       http://www.apache.org/licenses/LICENSE-2.0
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+
+How to build PlatformIO based project
+=====================================
+
+1. `Install PlatformIO Core <http://docs.platformio.org/page/core.html>`_
+2. Download `development platform with examples <https://github.com/platformio/platform-espressif32/archive/develop.zip>`_
+3. Extract ZIP archive
+4. Run these commands:
+
+.. code-block:: bash
+
+    # Change directory to example
+    > cd platform-espressif32/examples/espidf-ulp-adc
+
+    # Build project
+    > platformio run
+
+    # Upload firmware
+    > platformio run --target upload
+
+    # Build specific environment
+    > platformio run -e esp32dev
+
+    # Upload firmware for the specific environment
+    > platformio run -e esp32dev --target upload
+
+    # Clean build files
+    > platformio run --target clean
diff --git a/examples/espidf-ulp-adc/include/README b/examples/espidf-ulp-adc/include/README
new file mode 100644
index 0000000..194dcd4
--- /dev/null
+++ b/examples/espidf-ulp-adc/include/README
@@ -0,0 +1,39 @@
+
+This directory is intended for project header files.
+
+A header file is a file containing C declarations and macro definitions
+to be shared between several project source files. You request the use of a
+header file in your project source file (C, C++, etc) located in `src` folder
+by including it, with the C preprocessing directive `#include'.
+
+```src/main.c
+
+#include "header.h"
+
+int main (void)
+{
+ ...
+}
+```
+
+Including a header file produces the same results as copying the header file
+into each source file that needs it. Such copying would be time-consuming
+and error-prone. With a header file, the related declarations appear
+in only one place. If they need to be changed, they can be changed in one
+place, and programs that include the header file will automatically use the
+new version when next recompiled. The header file eliminates the labor of
+finding and changing all the copies as well as the risk that a failure to
+find one copy will result in inconsistencies within a program.
+
+In C, the usual convention is to give header files names that end with `.h'.
+It is most portable to use only letters, digits, dashes, and underscores in
+header file names, and at most one dot.
+
+Read more about using header files in official GCC documentation:
+
+* Include Syntax
+* Include Operation
+* Once-Only Headers
+* Computed Includes
+
+https://gcc.gnu.org/onlinedocs/cpp/Header-Files.html
diff --git a/examples/espidf-ulp-adc/lib/README b/examples/espidf-ulp-adc/lib/README
new file mode 100644
index 0000000..6debab1
--- /dev/null
+++ b/examples/espidf-ulp-adc/lib/README
@@ -0,0 +1,46 @@
+
+This directory is intended for project specific (private) libraries.
+PlatformIO will compile them to static libraries and link into executable file.
+
+The source code of each library should be placed in a an own separate directory
+("lib/your_library_name/[here are source files]").
+
+For example, see a structure of the following two libraries `Foo` and `Bar`:
+
+|--lib
+|  |
+|  |--Bar
+|  |  |--docs
+|  |  |--examples
+|  |  |--src
+|  |     |- Bar.c
+|  |     |- Bar.h
+|  |  |- library.json (optional, custom build options, etc) https://docs.platformio.org/page/librarymanager/config.html
+|  |
+|  |--Foo
+|  |  |- Foo.c
+|  |  |- Foo.h
+|  |
+|  |- README --> THIS FILE
+|
+|- platformio.ini
+|--src
+   |- main.c
+
+and a contents of `src/main.c`:
+```
+#include <Foo.h>
+#include <Bar.h>
+
+int main (void)
+{
+  ...
+}
+
+```
+
+PlatformIO Library Dependency Finder will find automatically dependent
+libraries scanning project source files.
+
+More information about PlatformIO Library Dependency Finder
+- https://docs.platformio.org/page/librarymanager/ldf.html
diff --git a/examples/espidf-ulp-adc/platformio.ini b/examples/espidf-ulp-adc/platformio.ini
new file mode 100644
index 0000000..cf23761
--- /dev/null
+++ b/examples/espidf-ulp-adc/platformio.ini
@@ -0,0 +1,14 @@
+; PlatformIO Project Configuration File
+;
+;   Build options: build flags, source filter, extra scripting
+;   Upload options: custom port, speed and extra flags
+;   Library options: dependencies, extra library storages
+;
+; Please visit documentation for the other options and examples
+; http://docs.platformio.org/page/projectconf.html
+
+[env:esp32dev]
+platform = espressif32
+framework = espidf
+board = esp32dev
+build_flags = -DCONFIG_WIFI_SSID=\"ESP_AP\" -DCONFIG_WIFI_PASSWORD=\"MYPASS\"
diff --git a/examples/espidf-ulp-adc/src/sdkconfig.h b/examples/espidf-ulp-adc/src/sdkconfig.h
new file mode 100644
index 0000000..a278aa1
--- /dev/null
+++ b/examples/espidf-ulp-adc/src/sdkconfig.h
@@ -0,0 +1,349 @@
+/*
+ *
+ * Automatically generated file; DO NOT EDIT.
+ * Espressif IoT Development Framework Configuration
+ *
+ */
+#define CONFIG_ULP_COPROC_ENABLED 1
+#define CONFIG_ULP_COPROC_RESERVE_MEM 1024
+#define CONFIG_GATTC_ENABLE 1
+#define CONFIG_ESP32_PHY_MAX_TX_POWER 20
+#define CONFIG_TRACEMEM_RESERVE_DRAM 0x0
+#define CONFIG_FREERTOS_MAX_TASK_NAME_LEN 16
+#define CONFIG_MQTT_TRANSPORT_SSL 1
+#define CONFIG_BLE_SMP_ENABLE 1
+#define CONFIG_SDP_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MB_SERIAL_TASK_PRIO 10
+#define CONFIG_MQTT_PROTOCOL_311 1
+#define CONFIG_TCP_RECVMBOX_SIZE 6
+#define CONFIG_FATFS_CODEPAGE_437 1
+#define CONFIG_BLE_SCAN_DUPLICATE 1
+#define CONFIG_AVDT_TRACE_LEVEL_WARNING 1
+#define CONFIG_AWS_IOT_SHADOW_MAX_SIMULTANEOUS_ACKS 10
+#define CONFIG_TCP_WND_DEFAULT 5744
+#define CONFIG_PARTITION_TABLE_OFFSET 0x8000
+#define CONFIG_SW_COEXIST_ENABLE 1
+#define CONFIG_SPIFFS_USE_MAGIC_LENGTH 1
+#define CONFIG_AVCT_INITIAL_TRACE_LEVEL 2
+#define CONFIG_IPC_TASK_STACK_SIZE 1024
+#define CONFIG_FATFS_PER_FILE_CACHE 1
+#define CONFIG_ESPTOOLPY_FLASHFREQ "40m"
+#define CONFIG_AWS_IOT_SHADOW_MAX_SIZE_OF_THING_NAME 20
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_RSA 1
+#define CONFIG_UDP_RECVMBOX_SIZE 6
+#define CONFIG_FREERTOS_QUEUE_REGISTRY_SIZE 0
+#define CONFIG_MBEDTLS_AES_C 1
+#define CONFIG_MBEDTLS_ECP_DP_SECP521R1_ENABLED 1
+#define CONFIG_ESP32_WIFI_SOFTAP_BEACON_MAX_LEN 752
+#define CONFIG_MBEDTLS_GCM_C 1
+#define CONFIG_ESPTOOLPY_FLASHSIZE "2MB"
+#define CONFIG_HEAP_POISONING_DISABLED 1
+#define CONFIG_SPIFFS_CACHE_WR 1
+#define CONFIG_BROWNOUT_DET_LVL_SEL_0 1
+#define CONFIG_ESP32_WIFI_DYNAMIC_TX_BUFFER 1
+#define CONFIG_EMAC_L2_TO_L3_RX_BUF_MODE 1
+#define CONFIG_BTDM_CONTROLLER_MODEM_SLEEP 1
+#define CONFIG_SPIFFS_CACHE 1
+#define CONFIG_INT_WDT 1
+#define CONFIG_BTDM_CONTROLLER_BLE_MAX_CONN 3
+#define CONFIG_MBEDTLS_SSL_PROTO_TLS1 1
+#define CONFIG_ESP_GRATUITOUS_ARP 1
+#define CONFIG_AWS_IOT_SHADOW_MAX_SIZE_OF_UNIQUE_CLIENT_ID_BYTES 80
+#define CONFIG_MBEDTLS_ECDSA_C 1
+#define CONFIG_ESPTOOLPY_FLASHFREQ_40M 1
+#define CONFIG_LOG_BOOTLOADER_LEVEL_INFO 1
+#define CONFIG_ESPTOOLPY_FLASHSIZE_2MB 1
+#define CONFIG_HTTPD_MAX_REQ_HDR_LEN 512
+#define CONFIG_BTDM_CONTROLLER_PINNED_TO_CORE 0
+#define CONFIG_AWS_IOT_MQTT_PORT 8883
+#define CONFIG_FREERTOS_THREAD_LOCAL_STORAGE_POINTERS 1
+#define CONFIG_MBEDTLS_ECDH_C 1
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_ELLIPTIC_CURVE 1
+#define CONFIG_ESP32_WIFI_STATIC_RX_BUFFER_NUM 10
+#define CONFIG_AWS_IOT_MQTT_MAX_RECONNECT_WAIT_INTERVAL 128000
+#define CONFIG_MBEDTLS_SSL_ALPN 1
+#define CONFIG_BTM_TRACE_LEVEL_WARNING 1
+#define CONFIG_MBEDTLS_PEM_WRITE_C 1
+#define CONFIG_MBEDTLS_SSL_OUT_CONTENT_LEN 4096
+#define CONFIG_RFCOMM_TRACE_LEVEL_WARNING 1
+#define CONFIG_LOG_DEFAULT_LEVEL_INFO 1
+#define CONFIG_BT_RESERVE_DRAM 0xdb5c
+#define CONFIG_FATFS_FS_LOCK 0
+#define CONFIG_IP_LOST_TIMER_INTERVAL 120
+#define CONFIG_SPIFFS_META_LENGTH 4
+#define CONFIG_ESP32_PANIC_PRINT_REBOOT 1
+#define CONFIG_MB_CONTROLLER_NOTIFY_QUEUE_SIZE 20
+#define CONFIG_MBEDTLS_ECP_DP_BP384R1_ENABLED 1
+#define CONFIG_MBEDTLS_ECP_DP_SECP256K1_ENABLED 1
+#define CONFIG_AWS_IOT_MQTT_RX_BUF_LEN 512
+#define CONFIG_MB_SERIAL_BUF_SIZE 256
+#define CONFIG_CONSOLE_UART_BAUDRATE 115200
+#define CONFIG_LWIP_MAX_SOCKETS 10
+#define CONFIG_LWIP_NETIF_LOOPBACK 1
+#define CONFIG_MCA_TRACE_LEVEL_WARNING 1
+#define CONFIG_EMAC_TASK_PRIORITY 20
+#define CONFIG_TIMER_TASK_STACK_DEPTH 2048
+#define CONFIG_TCP_MSS 1436
+#define CONFIG_MBEDTLS_ECP_DP_CURVE25519_ENABLED 1
+#define CONFIG_BTIF_INITIAL_TRACE_LEVEL 2
+#define CONFIG_BTDM_CONTROLLER_BLE_MAX_CONN_EFF 3
+#define CONFIG_FATFS_CODEPAGE 437
+#define CONFIG_APPL_TRACE_LEVEL_WARNING 1
+#define CONFIG_BTC_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ESP32_DEFAULT_CPU_FREQ_160 1
+#define CONFIG_LWIP_MAX_UDP_PCBS 16
+#define CONFIG_ESPTOOLPY_BAUD 115200
+#define CONFIG_INT_WDT_CHECK_CPU1 1
+#define CONFIG_AVRC_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ADC_CAL_LUT_ENABLE 1
+#define CONFIG_AWS_IOT_MQTT_TX_BUF_LEN 512
+#define CONFIG_FLASHMODE_DIO 1
+#define CONFIG_ESPTOOLPY_AFTER_RESET 1
+#define CONFIG_OPTIMIZATION_ASSERTIONS_ENABLED 1
+#define CONFIG_LWIP_DHCPS_MAX_STATION_NUM 8
+#define CONFIG_TOOLPREFIX "xtensa-esp32-elf-"
+#define CONFIG_MBEDTLS_ECP_C 1
+#define CONFIG_FREERTOS_IDLE_TASK_STACKSIZE 1536
+#define CONFIG_MBEDTLS_RC4_DISABLED 1
+#define CONFIG_GAP_TRACE_LEVEL_WARNING 1
+#define CONFIG_CONSOLE_UART_NUM 0
+#define CONFIG_AWS_IOT_SHADOW_MAX_JSON_TOKEN_EXPECTED 120
+#define CONFIG_ESP32_APPTRACE_LOCK_ENABLE 1
+#define CONFIG_PTHREAD_STACK_MIN 768
+#define CONFIG_ESP32_RTC_CLOCK_SOURCE_INTERNAL_RC 1
+#define CONFIG_ESPTOOLPY_BAUD_115200B 1
+#define CONFIG_TCP_OVERSIZE_MSS 1
+#define CONFIG_FOUR_UNIVERSAL_MAC_ADDRESS 1
+#define CONFIG_CONSOLE_UART_DEFAULT 1
+#define CONFIG_NUMBER_OF_UNIVERSAL_MAC_ADDRESS 4
+#define CONFIG_GATT_TRACE_LEVEL_WARNING 1
+#define CONFIG_ESPTOOLPY_FLASHSIZE_DETECT 1
+#define CONFIG_EXAMPLE_EMBEDDED_CERTS 1
+#define CONFIG_TIMER_TASK_STACK_SIZE 3584
+#define CONFIG_BTIF_TRACE_LEVEL_WARNING 1
+#define CONFIG_ESP32_ENABLE_COREDUMP_TO_NONE 1
+#define CONFIG_HCI_INITIAL_TRACE_LEVEL 2
+#define CONFIG_AVDT_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MBEDTLS_X509_CRL_PARSE_C 1
+#define CONFIG_SCAN_DUPLICATE_BY_DEVICE_ADDR 1
+#define CONFIG_AWS_IOT_SHADOW_MAX_SHADOW_TOPIC_LENGTH_WITHOUT_THINGNAME 60
+#define CONFIG_MB_SERIAL_TASK_STACK_SIZE 2048
+#define CONFIG_GATTS_SEND_SERVICE_CHANGE_AUTO 1
+#define CONFIG_LWIP_DHCPS_LEASE_UNIT 60
+#define CONFIG_SPIFFS_USE_MAGIC 1
+#define CONFIG_TCPIP_TASK_STACK_SIZE 3072
+#define CONFIG_BLUFI_TRACE_LEVEL_WARNING 1
+#define CONFIG_BLUEDROID_PINNED_TO_CORE_0 1
+#define CONFIG_TASK_WDT 1
+#define CONFIG_RFCOMM_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MAIN_TASK_STACK_SIZE 3584
+#define CONFIG_SPIFFS_PAGE_CHECK 1
+#define CONFIG_ESP32_WIFI_TASK_PINNED_TO_CORE_0 1
+#define CONFIG_LWIP_MAX_ACTIVE_TCP 16
+#define CONFIG_TASK_WDT_TIMEOUT_S 5
+#define CONFIG_INT_WDT_TIMEOUT_MS 300
+#define CONFIG_ESPTOOLPY_FLASHMODE "dio"
+#define CONFIG_BTC_TASK_STACK_SIZE 3072
+#define CONFIG_BLUEDROID_ENABLED 1
+#define CONFIG_NEWLIB_STDIN_LINE_ENDING_CR 1
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_ECDH_RSA 1
+#define CONFIG_ESPTOOLPY_BEFORE "default_reset"
+#define CONFIG_ADC2_DISABLE_DAC 1
+#define CONFIG_FATFS_LFN_HEAP 1
+#define CONFIG_BLE_ADV_REPORT_FLOW_CONTROL_NUM 100
+#define CONFIG_LOG_DEFAULT_LEVEL 3
+#define CONFIG_FREERTOS_ASSERT_ON_UNTESTED_FUNCTION 1
+#define CONFIG_TIMER_QUEUE_LENGTH 10
+#define CONFIG_SUPPRESS_SELECT_DEBUG_OUTPUT 1
+#define CONFIG_GATTS_SEND_SERVICE_CHANGE_MODE 0
+#define CONFIG_TCPIP_TASK_AFFINITY_NO_AFFINITY 1
+#define CONFIG_MAKE_WARN_UNDEFINED_VARIABLES 1
+#define CONFIG_FATFS_TIMEOUT_MS 10000
+#define CONFIG_ESP32_WIFI_DYNAMIC_RX_BUFFER_NUM 32
+#define CONFIG_ESP_HTTP_CLIENT_ENABLE_HTTPS 1
+#define CONFIG_PAN_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MBEDTLS_CCM_C 1
+#define CONFIG_SPI_MASTER_ISR_IN_IRAM 1
+#define CONFIG_MCA_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ESP32_PHY_MAX_WIFI_TX_POWER 20
+#define CONFIG_A2D_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ESP32_RTC_CLK_CAL_CYCLES 1024
+#define CONFIG_ESP32_WIFI_TX_BA_WIN 6
+#define CONFIG_ESP32_WIFI_NVS_ENABLED 1
+#define CONFIG_MDNS_MAX_SERVICES 10
+#define CONFIG_EMAC_CHECK_LINK_PERIOD_MS 2000
+#define CONFIG_BTDM_LPCLK_SEL_MAIN_XTAL 1
+#define CONFIG_MBEDTLS_ECP_DP_SECP224R1_ENABLED 1
+#define CONFIG_LIBSODIUM_USE_MBEDTLS_SHA 1
+#define CONFIG_AWS_IOT_SDK 1
+#define CONFIG_DMA_RX_BUF_NUM 10
+#define CONFIG_MBEDTLS_ECP_DP_SECP384R1_ENABLED 1
+#define CONFIG_TCP_SYNMAXRTX 6
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA 1
+#define CONFIG_BTDM_CONTROLLER_BR_EDR_MAX_SYNC_CONN_EFF 0
+#define CONFIG_PYTHON "python"
+#define CONFIG_MBEDTLS_ECP_NIST_OPTIM 1
+#define CONFIG_ESP32_TIME_SYSCALL_USE_RTC_FRC1 1
+#define CONFIG_ESPTOOLPY_COMPRESSED 1
+#define CONFIG_PARTITION_TABLE_FILENAME "partitions_singleapp.csv"
+#define CONFIG_MB_CONTROLLER_STACK_SIZE 4096
+#define CONFIG_TCP_SND_BUF_DEFAULT 5744
+#define CONFIG_GARP_TMR_INTERVAL 60
+#define CONFIG_LWIP_DHCP_MAX_NTP_SERVERS 1
+#define CONFIG_BNEP_INITIAL_TRACE_LEVEL 2
+#define CONFIG_HCI_TRACE_LEVEL_WARNING 1
+#define CONFIG_TCP_MSL 60000
+#define CONFIG_MBEDTLS_SSL_PROTO_TLS1_1 1
+#define CONFIG_LWIP_SO_REUSE_RXTOALL 1
+#define CONFIG_MB_CONTROLLER_NOTIFY_TIMEOUT 20
+#define CONFIG_PARTITION_TABLE_SINGLE_APP 1
+#define CONFIG_ESP32_WIFI_RX_BA_WIN 6
+#define CONFIG_MBEDTLS_X509_CSR_PARSE_C 1
+#define CONFIG_SPIFFS_USE_MTIME 1
+#define CONFIG_BTC_TRACE_LEVEL_WARNING 1
+#define CONFIG_EMAC_TASK_STACK_SIZE 3072
+#define CONFIG_SMP_TRACE_LEVEL_WARNING 1
+#define CONFIG_MB_QUEUE_LENGTH 20
+#define CONFIG_SW_COEXIST_PREFERENCE_VALUE 2
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_ECDHE_RSA 1
+#define CONFIG_LWIP_DHCP_DOES_ARP_CHECK 1
+#define CONFIG_FREERTOS_TASK_FUNCTION_WRAPPER 1
+#define CONFIG_SYSTEM_EVENT_TASK_STACK_SIZE 2304
+#define CONFIG_BOOTLOADER_VDDSDIO_BOOST_1_9V 1
+#define CONFIG_A2D_TRACE_LEVEL_WARNING 1
+#define CONFIG_ESP32_DEEP_SLEEP_WAKEUP_DELAY 2000
+#define CONFIG_AWS_IOT_MQTT_NUM_SUBSCRIBE_HANDLERS 5
+#define CONFIG_BROWNOUT_DET_LVL 0
+#define CONFIG_MBEDTLS_PEM_PARSE_C 1
+#define CONFIG_SPIFFS_GC_MAX_RUNS 10
+#define CONFIG_ESP32_APPTRACE_DEST_NONE 1
+#define CONFIG_MBEDTLS_INTERNAL_MEM_ALLOC 1
+#define CONFIG_MBEDTLS_SSL_PROTO_TLS1_2 1
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_DHE_RSA 1
+#define CONFIG_ESP32_WIFI_DYNAMIC_TX_BUFFER_NUM 32
+#define CONFIG_HTTPD_MAX_URI_LEN 512
+#define CONFIG_MBEDTLS_ECP_DP_BP256R1_ENABLED 1
+#define CONFIG_AVCT_TRACE_LEVEL_WARNING 1
+#define CONFIG_MBEDTLS_ECP_DP_SECP224K1_ENABLED 1
+#define CONFIG_TASK_WDT_CHECK_IDLE_TASK_CPU1 1
+#define CONFIG_ESP32_DEFAULT_CPU_FREQ_MHZ 160
+#define CONFIG_MBEDTLS_HARDWARE_AES 1
+#define CONFIG_FREERTOS_HZ 100
+#define CONFIG_LOG_COLORS 1
+#define CONFIG_OSI_TRACE_LEVEL_WARNING 1
+#define CONFIG_ESP32_PHY_CALIBRATION_AND_DATA_STORAGE 1
+#define CONFIG_STACK_CHECK_NONE 1
+#define CONFIG_ADC_CAL_EFUSE_TP_ENABLE 1
+#define CONFIG_BNEP_TRACE_LEVEL_WARNING 1
+#define CONFIG_FREERTOS_ASSERT_FAIL_ABORT 1
+#define CONFIG_BROWNOUT_DET 1
+#define CONFIG_AWS_IOT_SHADOW_MAX_SIMULTANEOUS_THINGNAMES 10
+#define CONFIG_ESP32_XTAL_FREQ 40
+#define CONFIG_OSI_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MONITOR_BAUD_115200B 1
+#define CONFIG_LOG_BOOTLOADER_LEVEL 3
+#define CONFIG_MBEDTLS_TLS_ENABLED 1
+#define CONFIG_LWIP_MAX_RAW_PCBS 16
+#define CONFIG_SMP_ENABLE 1
+#define CONFIG_HID_TRACE_LEVEL_WARNING 1
+#define CONFIG_AVRC_TRACE_LEVEL_WARNING 1
+#define CONFIG_MBEDTLS_SSL_SESSION_TICKETS 1
+#define CONFIG_SPIFFS_MAX_PARTITIONS 3
+#define CONFIG_ESP_ERR_TO_NAME_LOOKUP 1
+#define CONFIG_BTDM_CONTROLLER_PINNED_TO_CORE_0 1
+#define CONFIG_MBEDTLS_SSL_RENEGOTIATION 1
+#define CONFIG_HID_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ESPTOOLPY_BEFORE_RESET 1
+#define CONFIG_MB_EVENT_QUEUE_TIMEOUT 20
+#define CONFIG_ESPTOOLPY_BAUD_OTHER_VAL 115200
+#define CONFIG_AWS_EXAMPLE_CLIENT_ID "myesp32"
+#define CONFIG_SPIFFS_OBJ_NAME_LEN 32
+#define CONFIG_ESP32_PTHREAD_TASK_PRIO_DEFAULT 5
+#define CONFIG_BTDM_CONTROLLER_BR_EDR_MAX_ACL_CONN_EFF 0
+#define CONFIG_PARTITION_TABLE_MD5 1
+#define CONFIG_TCPIP_RECVMBOX_SIZE 32
+#define CONFIG_TCP_MAXRTX 12
+#define CONFIG_BTM_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ESPTOOLPY_AFTER "hard_reset"
+#define CONFIG_TCPIP_TASK_AFFINITY 0x7FFFFFFF
+#define CONFIG_LWIP_SO_REUSE 1
+#define CONFIG_ESP32_XTAL_FREQ_40 1
+#define CONFIG_BTDM_CONTROLLER_MODE_BLE_ONLY 1
+#define CONFIG_DMA_TX_BUF_NUM 10
+#define CONFIG_LWIP_MAX_LISTENING_TCP 16
+#define CONFIG_FREERTOS_INTERRUPT_BACKTRACE 1
+#define CONFIG_WL_SECTOR_SIZE 4096
+#define CONFIG_ESP32_DEBUG_OCDAWARE 1
+#define CONFIG_MQTT_TRANSPORT_WEBSOCKET 1
+#define CONFIG_TIMER_TASK_PRIORITY 1
+#define CONFIG_MBEDTLS_TLS_CLIENT 1
+#define CONFIG_AWS_IOT_MQTT_MIN_RECONNECT_WAIT_INTERVAL 1000
+#define CONFIG_BTDM_CONTROLLER_HCI_MODE_VHCI 1
+#define CONFIG_BT_ENABLED 1
+#define CONFIG_SDP_TRACE_LEVEL_WARNING 1
+#define CONFIG_SW_COEXIST_PREFERENCE_BALANCE 1
+#define CONFIG_MBEDTLS_ECP_DP_SECP256R1_ENABLED 1
+#define CONFIG_MONITOR_BAUD 115200
+#define CONFIG_ESP32_DEBUG_STUBS_ENABLE 1
+#define CONFIG_TCPIP_LWIP 1
+#define CONFIG_REDUCE_PHY_TX_POWER 1
+#define CONFIG_BOOTLOADER_WDT_TIME_MS 9000
+#define CONFIG_PAN_TRACE_LEVEL_WARNING 1
+#define CONFIG_FREERTOS_CORETIMER_0 1
+#define CONFIG_PARTITION_TABLE_CUSTOM_FILENAME "partitions.csv"
+#define CONFIG_MBEDTLS_HAVE_TIME 1
+#define CONFIG_FREERTOS_CHECK_STACKOVERFLOW_CANARY 1
+#define CONFIG_TCP_QUEUE_OOSEQ 1
+#define CONFIG_GATTS_ENABLE 1
+#define CONFIG_ADC_CAL_EFUSE_VREF_ENABLE 1
+#define CONFIG_MBEDTLS_TLS_SERVER 1
+#define CONFIG_MBEDTLS_TLS_SERVER_AND_CLIENT 1
+#define CONFIG_BLE_ADV_REPORT_FLOW_CONTROL_SUPPORTED 1
+#define CONFIG_FREERTOS_ISR_STACKSIZE 1536
+#define CONFIG_SUPPORT_TERMIOS 1
+#define CONFIG_OPENSSL_ASSERT_DO_NOTHING 1
+#define CONFIG_WL_SECTOR_SIZE_4096 1
+#define CONFIG_OPTIMIZATION_LEVEL_DEBUG 1
+#define CONFIG_GATT_INITIAL_TRACE_LEVEL 2
+#define CONFIG_FREERTOS_NO_AFFINITY 0x7FFFFFFF
+#define CONFIG_AWS_IOT_MQTT_HOST ""
+#define CONFIG_L2CAP_TRACE_LEVEL_WARNING 1
+#define CONFIG_ESP32_WIFI_AMPDU_TX_ENABLED 1
+#define CONFIG_MB_TIMER_INDEX 0
+#define CONFIG_SCAN_DUPLICATE_TYPE 0
+#define CONFIG_MBEDTLS_ECP_DP_SECP192R1_ENABLED 1
+#define CONFIG_APPL_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MBEDTLS_ECP_DP_BP512R1_ENABLED 1
+#define CONFIG_SMP_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA 1
+#define CONFIG_SPI_SLAVE_ISR_IN_IRAM 1
+#define CONFIG_L2CAP_INITIAL_TRACE_LEVEL 2
+#define CONFIG_SYSTEM_EVENT_QUEUE_SIZE 32
+#define CONFIG_BT_ACL_CONNECTIONS 4
+#define CONFIG_FATFS_MAX_LFN 255
+#define CONFIG_ESP32_WIFI_TX_BUFFER_TYPE 1
+#define CONFIG_BOOTLOADER_WDT_ENABLE 1
+#define CONFIG_GAP_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ESP32_WIFI_AMPDU_RX_ENABLED 1
+#define CONFIG_LWIP_LOOPBACK_MAX_PBUFS 8
+#define CONFIG_MBEDTLS_SSL_IN_CONTENT_LEN 16384
+#define CONFIG_MB_TIMER_GROUP 0
+#define CONFIG_SPI_FLASH_ROM_DRIVER_PATCH 1
+#define CONFIG_MQTT_TRANSPORT_WEBSOCKET_SECURE 1
+#define CONFIG_SPIFFS_PAGE_SIZE 256
+#define CONFIG_MBEDTLS_ECP_DP_SECP192K1_ENABLED 1
+#define CONFIG_TASK_WDT_CHECK_IDLE_TASK_CPU0 1
+#define CONFIG_ESP32_PTHREAD_TASK_STACK_SIZE_DEFAULT 3072
+#define CONFIG_MB_TIMER_PORT_ENABLED 1
+#define CONFIG_DUPLICATE_SCAN_CACHE_SIZE 200
+#define CONFIG_MONITOR_BAUD_OTHER_VAL 115200
+#define CONFIG_NEWLIB_STDOUT_LINE_ENDING_CRLF 1
+#define CONFIG_ESPTOOLPY_PORT "/dev/ttyUSB0"
+#define CONFIG_SPI_FLASH_WRITING_DANGEROUS_REGIONS_ABORTS 1
+#define CONFIG_MBEDTLS_ASYMMETRIC_CONTENT_LEN 1
+#define CONFIG_BLE_ADV_REPORT_DISCARD_THRSHOLD 20
+#define CONFIG_BLUEDROID_PINNED_TO_CORE 0
+#define CONFIG_BTDM_MODEM_SLEEP_MODE_ORIG 1
+#define CONFIG_ESP32_WIFI_IRAM_OPT 1
+#define CONFIG_BLUFI_INITIAL_TRACE_LEVEL 2
+#define CONFIG_FATFS_API_ENCODING_ANSI_OEM 1
diff --git a/examples/espidf-ulp-adc/src/ulp_adc_example_main.c b/examples/espidf-ulp-adc/src/ulp_adc_example_main.c
new file mode 100644
index 0000000..b0347dc
--- /dev/null
+++ b/examples/espidf-ulp-adc/src/ulp_adc_example_main.c
@@ -0,0 +1,94 @@
+/* ULP Example
+
+   This example code is in the Public Domain (or CC0 licensed, at your option.)
+
+   Unless required by applicable law or agreed to in writing, this
+   software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+   CONDITIONS OF ANY KIND, either express or implied.
+*/
+
+#include <stdio.h>
+#include <string.h>
+#include "esp_sleep.h"
+#include "nvs.h"
+#include "nvs_flash.h"
+#include "soc/rtc_cntl_reg.h"
+#include "soc/sens_reg.h"
+#include "driver/gpio.h"
+#include "driver/rtc_io.h"
+#include "driver/adc.h"
+#include "driver/dac.h"
+#include "esp32/ulp.h"
+#include "ulp_main.h"
+
+extern const uint8_t ulp_main_bin_start[] asm("_binary_ulp_main_bin_start");
+extern const uint8_t ulp_main_bin_end[]   asm("_binary_ulp_main_bin_end");
+
+/* This function is called once after power-on reset, to load ULP program into
+ * RTC memory and configure the ADC.
+ */
+static void init_ulp_program();
+
+/* This function is called every time before going into deep sleep.
+ * It starts the ULP program and resets measurement counter.
+ */
+static void start_ulp_program();
+
+void app_main()
+{
+    esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
+    if (cause != ESP_SLEEP_WAKEUP_ULP) {
+        printf("Not ULP wakeup\n");
+        init_ulp_program();
+    } else {
+        printf("Deep sleep wakeup\n");
+        printf("ULP did %d measurements since last reset\n", ulp_sample_counter & UINT16_MAX);
+        printf("Thresholds:  low=%d  high=%d\n", ulp_low_thr, ulp_high_thr);
+        ulp_last_result &= UINT16_MAX;
+        printf("Value=%d was %s threshold\n", ulp_last_result,
+                ulp_last_result < ulp_low_thr ? "below" : "above");
+    }
+    printf("Entering deep sleep\n\n");
+    start_ulp_program();
+    ESP_ERROR_CHECK( esp_sleep_enable_ulp_wakeup() );
+    esp_deep_sleep_start();
+}
+
+static void init_ulp_program()
+{
+    esp_err_t err = ulp_load_binary(0, ulp_main_bin_start,
+            (ulp_main_bin_end - ulp_main_bin_start) / sizeof(uint32_t));
+    ESP_ERROR_CHECK(err);
+
+    /* Configure ADC channel */
+    /* Note: when changing channel here, also change 'adc_channel' constant
+       in adc.S */
+    adc1_config_channel_atten(ADC1_CHANNEL_6, ADC_ATTEN_DB_11);
+    adc1_config_width(ADC_WIDTH_BIT_12);
+    adc1_ulp_enable();
+
+    /* Set low and high thresholds, approx. 1.35V - 1.75V*/
+    ulp_low_thr = 1500;
+    ulp_high_thr = 2000;
+
+    /* Set ULP wake up period to 20ms */
+    ulp_set_wakeup_period(0, 2000000);
+
+    /* Disconnect GPIO12 and GPIO15 to remove current drain through
+     * pullup/pulldown resistors.
+     * GPIO12 may be pulled high to select flash voltage.
+     */
+    rtc_gpio_isolate(GPIO_NUM_12);
+    rtc_gpio_isolate(GPIO_NUM_15);
+    esp_deep_sleep_disable_rom_logging(); // suppress boot messages
+}
+
+static void start_ulp_program()
+{
+    /* Reset sample counter */
+    ulp_sample_counter = 0;
+
+    /* Start the program */
+    esp_err_t err = ulp_run(&ulp_entry - RTC_SLOW_MEM);
+    ESP_ERROR_CHECK(err);
+}
diff --git a/examples/espidf-ulp-adc/test/README b/examples/espidf-ulp-adc/test/README
new file mode 100644
index 0000000..df5066e
--- /dev/null
+++ b/examples/espidf-ulp-adc/test/README
@@ -0,0 +1,11 @@
+
+This directory is intended for PIO Unit Testing and project tests.
+
+Unit Testing is a software testing method by which individual units of
+source code, sets of one or more MCU program modules together with associated
+control data, usage procedures, and operating procedures, are tested to
+determine whether they are fit for use. Unit testing finds problems early
+in the development cycle.
+
+More information about PIO Unit Testing:
+- https://docs.platformio.org/page/plus/unit-testing.html
diff --git a/examples/espidf-ulp-adc/ulp/adc.S b/examples/espidf-ulp-adc/ulp/adc.S
new file mode 100644
index 0000000..70d0439
--- /dev/null
+++ b/examples/espidf-ulp-adc/ulp/adc.S
@@ -0,0 +1,115 @@
+/* ULP Example: using ADC in deep sleep
+
+   This example code is in the Public Domain (or CC0 licensed, at your option.)
+
+   Unless required by applicable law or agreed to in writing, this
+   software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+   CONDITIONS OF ANY KIND, either express or implied.
+
+   This file contains assembly code which runs on the ULP.
+
+   ULP wakes up to run this code at a certain period, determined by the values
+   in SENS_ULP_CP_SLEEP_CYCx_REG registers. On each wake up, the program
+   measures input voltage on the given ADC channel 'adc_oversampling_factor'
+   times. Measurements are accumulated and average value is calculated.
+   Average value is compared to the two thresholds: 'low_thr' and 'high_thr'.
+   If the value is less than 'low_thr' or more than 'high_thr', ULP wakes up
+   the chip from deep sleep.
+*/
+
+/* ULP assembly files are passed through C preprocessor first, so include directives
+   and C macros may be used in these files 
+ */
+#include "soc/rtc_cntl_reg.h"
+#include "soc/soc_ulp.h"
+
+	/* ADC1 channel 6, GPIO34 */
+	.set adc_channel, 6
+
+	/* Configure the number of ADC samples to average on each measurement.
+	   For convenience, make it a power of 2. */
+	.set adc_oversampling_factor_log, 2
+	.set adc_oversampling_factor, (1 << adc_oversampling_factor_log)
+
+	/* Define variables, which go into .bss section (zero-initialized data) */
+	.bss
+
+	/* Low threshold of ADC reading.
+	   Set by the main program. */
+	.global low_thr
+low_thr:
+	.long 0
+
+	/* High threshold of ADC reading.
+	   Set by the main program. */
+	.global high_thr
+high_thr:
+	.long 0
+
+	/* Counter of measurements done */
+	.global sample_counter
+sample_counter:
+	.long 0
+
+	.global last_result
+last_result:
+	.long 0
+
+	/* Code goes into .text section */
+	.text
+	.global entry
+entry:
+	/* increment sample counter */
+	move r3, sample_counter
+	ld r2, r3, 0
+	add r2, r2, 1
+	st r2, r3, 0
+
+	/* do measurements using ADC */
+	/* r0 will be used as accumulator */
+	move r0, 0
+	/* initialize the loop counter */
+	stage_rst
+measure:
+	/* measure and add value to accumulator */
+	adc r1, 0, adc_channel + 1
+	add r0, r0, r1
+	/* increment loop counter and check exit condition */
+	stage_inc 1
+	jumps measure, adc_oversampling_factor, lt
+
+	/* divide accumulator by adc_oversampling_factor.
+	   Since it is chosen as a power of two, use right shift */
+	rsh r0, r0, adc_oversampling_factor_log
+	/* averaged value is now in r0; store it into last_result */
+	move r3, last_result
+	st r0, r3, 0
+
+	/* compare with low_thr; wake up if value < low_thr */
+	move r3, low_thr
+	ld r3, r3, 0
+	sub r3, r0, r3
+	jump wake_up, ov
+
+	/* compare with high_thr; wake up if value > high_thr */
+	move r3, high_thr
+	ld r3, r3, 0
+	sub r3, r3, r0
+	jump wake_up, ov
+
+	/* value within range, end the program */
+	.global exit
+exit:
+	halt
+
+	.global wake_up
+wake_up:
+	/* Check if the system can be woken up */
+	READ_RTC_FIELD(RTC_CNTL_LOW_POWER_ST_REG, RTC_CNTL_RDY_FOR_WAKEUP)
+	and r0, r0, 1
+	jump exit, eq
+
+	/* Wake up the SoC, end program */
+	wake
+	WRITE_RTC_FIELD(RTC_CNTL_STATE0_REG, RTC_CNTL_ULP_CP_SLP_TIMER_EN, 0)
+	halt
diff --git a/examples/espidf-ulp-pulse/.gitignore b/examples/espidf-ulp-pulse/.gitignore
new file mode 100644
index 0000000..6c69f4c
--- /dev/null
+++ b/examples/espidf-ulp-pulse/.gitignore
@@ -0,0 +1,2 @@
+.pioenvs
+.piolibdeps
diff --git a/examples/espidf-ulp-pulse/.travis.yml b/examples/espidf-ulp-pulse/.travis.yml
new file mode 100644
index 0000000..7c486f1
--- /dev/null
+++ b/examples/espidf-ulp-pulse/.travis.yml
@@ -0,0 +1,67 @@
+# Continuous Integration (CI) is the practice, in software
+# engineering, of merging all developer working copies with a shared mainline
+# several times a day < https://docs.platformio.org/page/ci/index.html >
+#
+# Documentation:
+#
+# * Travis CI Embedded Builds with PlatformIO
+#   < https://docs.travis-ci.com/user/integration/platformio/ >
+#
+# * PlatformIO integration with Travis CI
+#   < https://docs.platformio.org/page/ci/travis.html >
+#
+# * User Guide for `platformio ci` command
+#   < https://docs.platformio.org/page/userguide/cmd_ci.html >
+#
+#
+# Please choose one of the following templates (proposed below) and uncomment
+# it (remove "# " before each line) or use own configuration according to the
+# Travis CI documentation (see above).
+#
+
+
+#
+# Template #1: General project. Test it using existing `platformio.ini`.
+#
+
+# language: python
+# python:
+#     - "2.7"
+#
+# sudo: false
+# cache:
+#     directories:
+#         - "~/.platformio"
+#
+# install:
+#     - pip install -U platformio
+#     - platformio update
+#
+# script:
+#     - platformio run
+
+
+#
+# Template #2: The project is intended to be used as a library with examples.
+#
+
+# language: python
+# python:
+#     - "2.7"
+#
+# sudo: false
+# cache:
+#     directories:
+#         - "~/.platformio"
+#
+# env:
+#     - PLATFORMIO_CI_SRC=path/to/test/file.c
+#     - PLATFORMIO_CI_SRC=examples/file.ino
+#     - PLATFORMIO_CI_SRC=path/to/test/directory
+#
+# install:
+#     - pip install -U platformio
+#     - platformio update
+#
+# script:
+#     - platformio ci --lib="." --board=ID_1 --board=ID_2 --board=ID_N
diff --git a/examples/espidf-ulp-pulse/README.rst b/examples/espidf-ulp-pulse/README.rst
new file mode 100644
index 0000000..ec7495b
--- /dev/null
+++ b/examples/espidf-ulp-pulse/README.rst
@@ -0,0 +1,38 @@
+..  Copyright 2014-present PlatformIO <contact@platformio.org>
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+       http://www.apache.org/licenses/LICENSE-2.0
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+
+How to build PlatformIO based project
+=====================================
+
+1. `Install PlatformIO Core <http://docs.platformio.org/page/core.html>`_
+2. Download `development platform with examples <https://github.com/platformio/platform-espressif32/archive/develop.zip>`_
+3. Extract ZIP archive
+4. Run these commands:
+
+.. code-block:: bash
+
+    # Change directory to example
+    > cd platform-espressif32/examples/espidf-ulp-pulse
+
+    # Build project
+    > platformio run
+
+    # Upload firmware
+    > platformio run --target upload
+
+    # Build specific environment
+    > platformio run -e esp32dev
+
+    # Upload firmware for the specific environment
+    > platformio run -e esp32dev --target upload
+
+    # Clean build files
+    > platformio run --target clean
diff --git a/examples/espidf-ulp-pulse/include/README b/examples/espidf-ulp-pulse/include/README
new file mode 100644
index 0000000..194dcd4
--- /dev/null
+++ b/examples/espidf-ulp-pulse/include/README
@@ -0,0 +1,39 @@
+
+This directory is intended for project header files.
+
+A header file is a file containing C declarations and macro definitions
+to be shared between several project source files. You request the use of a
+header file in your project source file (C, C++, etc) located in `src` folder
+by including it, with the C preprocessing directive `#include'.
+
+```src/main.c
+
+#include "header.h"
+
+int main (void)
+{
+ ...
+}
+```
+
+Including a header file produces the same results as copying the header file
+into each source file that needs it. Such copying would be time-consuming
+and error-prone. With a header file, the related declarations appear
+in only one place. If they need to be changed, they can be changed in one
+place, and programs that include the header file will automatically use the
+new version when next recompiled. The header file eliminates the labor of
+finding and changing all the copies as well as the risk that a failure to
+find one copy will result in inconsistencies within a program.
+
+In C, the usual convention is to give header files names that end with `.h'.
+It is most portable to use only letters, digits, dashes, and underscores in
+header file names, and at most one dot.
+
+Read more about using header files in official GCC documentation:
+
+* Include Syntax
+* Include Operation
+* Once-Only Headers
+* Computed Includes
+
+https://gcc.gnu.org/onlinedocs/cpp/Header-Files.html
diff --git a/examples/espidf-ulp-pulse/lib/README b/examples/espidf-ulp-pulse/lib/README
new file mode 100644
index 0000000..6debab1
--- /dev/null
+++ b/examples/espidf-ulp-pulse/lib/README
@@ -0,0 +1,46 @@
+
+This directory is intended for project specific (private) libraries.
+PlatformIO will compile them to static libraries and link into executable file.
+
+The source code of each library should be placed in a an own separate directory
+("lib/your_library_name/[here are source files]").
+
+For example, see a structure of the following two libraries `Foo` and `Bar`:
+
+|--lib
+|  |
+|  |--Bar
+|  |  |--docs
+|  |  |--examples
+|  |  |--src
+|  |     |- Bar.c
+|  |     |- Bar.h
+|  |  |- library.json (optional, custom build options, etc) https://docs.platformio.org/page/librarymanager/config.html
+|  |
+|  |--Foo
+|  |  |- Foo.c
+|  |  |- Foo.h
+|  |
+|  |- README --> THIS FILE
+|
+|- platformio.ini
+|--src
+   |- main.c
+
+and a contents of `src/main.c`:
+```
+#include <Foo.h>
+#include <Bar.h>
+
+int main (void)
+{
+  ...
+}
+
+```
+
+PlatformIO Library Dependency Finder will find automatically dependent
+libraries scanning project source files.
+
+More information about PlatformIO Library Dependency Finder
+- https://docs.platformio.org/page/librarymanager/ldf.html
diff --git a/examples/espidf-ulp-pulse/platformio.ini b/examples/espidf-ulp-pulse/platformio.ini
new file mode 100644
index 0000000..cf23761
--- /dev/null
+++ b/examples/espidf-ulp-pulse/platformio.ini
@@ -0,0 +1,14 @@
+; PlatformIO Project Configuration File
+;
+;   Build options: build flags, source filter, extra scripting
+;   Upload options: custom port, speed and extra flags
+;   Library options: dependencies, extra library storages
+;
+; Please visit documentation for the other options and examples
+; http://docs.platformio.org/page/projectconf.html
+
+[env:esp32dev]
+platform = espressif32
+framework = espidf
+board = esp32dev
+build_flags = -DCONFIG_WIFI_SSID=\"ESP_AP\" -DCONFIG_WIFI_PASSWORD=\"MYPASS\"
diff --git a/examples/espidf-ulp-pulse/src/sdkconfig.h b/examples/espidf-ulp-pulse/src/sdkconfig.h
new file mode 100644
index 0000000..a278aa1
--- /dev/null
+++ b/examples/espidf-ulp-pulse/src/sdkconfig.h
@@ -0,0 +1,349 @@
+/*
+ *
+ * Automatically generated file; DO NOT EDIT.
+ * Espressif IoT Development Framework Configuration
+ *
+ */
+#define CONFIG_ULP_COPROC_ENABLED 1
+#define CONFIG_ULP_COPROC_RESERVE_MEM 1024
+#define CONFIG_GATTC_ENABLE 1
+#define CONFIG_ESP32_PHY_MAX_TX_POWER 20
+#define CONFIG_TRACEMEM_RESERVE_DRAM 0x0
+#define CONFIG_FREERTOS_MAX_TASK_NAME_LEN 16
+#define CONFIG_MQTT_TRANSPORT_SSL 1
+#define CONFIG_BLE_SMP_ENABLE 1
+#define CONFIG_SDP_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MB_SERIAL_TASK_PRIO 10
+#define CONFIG_MQTT_PROTOCOL_311 1
+#define CONFIG_TCP_RECVMBOX_SIZE 6
+#define CONFIG_FATFS_CODEPAGE_437 1
+#define CONFIG_BLE_SCAN_DUPLICATE 1
+#define CONFIG_AVDT_TRACE_LEVEL_WARNING 1
+#define CONFIG_AWS_IOT_SHADOW_MAX_SIMULTANEOUS_ACKS 10
+#define CONFIG_TCP_WND_DEFAULT 5744
+#define CONFIG_PARTITION_TABLE_OFFSET 0x8000
+#define CONFIG_SW_COEXIST_ENABLE 1
+#define CONFIG_SPIFFS_USE_MAGIC_LENGTH 1
+#define CONFIG_AVCT_INITIAL_TRACE_LEVEL 2
+#define CONFIG_IPC_TASK_STACK_SIZE 1024
+#define CONFIG_FATFS_PER_FILE_CACHE 1
+#define CONFIG_ESPTOOLPY_FLASHFREQ "40m"
+#define CONFIG_AWS_IOT_SHADOW_MAX_SIZE_OF_THING_NAME 20
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_RSA 1
+#define CONFIG_UDP_RECVMBOX_SIZE 6
+#define CONFIG_FREERTOS_QUEUE_REGISTRY_SIZE 0
+#define CONFIG_MBEDTLS_AES_C 1
+#define CONFIG_MBEDTLS_ECP_DP_SECP521R1_ENABLED 1
+#define CONFIG_ESP32_WIFI_SOFTAP_BEACON_MAX_LEN 752
+#define CONFIG_MBEDTLS_GCM_C 1
+#define CONFIG_ESPTOOLPY_FLASHSIZE "2MB"
+#define CONFIG_HEAP_POISONING_DISABLED 1
+#define CONFIG_SPIFFS_CACHE_WR 1
+#define CONFIG_BROWNOUT_DET_LVL_SEL_0 1
+#define CONFIG_ESP32_WIFI_DYNAMIC_TX_BUFFER 1
+#define CONFIG_EMAC_L2_TO_L3_RX_BUF_MODE 1
+#define CONFIG_BTDM_CONTROLLER_MODEM_SLEEP 1
+#define CONFIG_SPIFFS_CACHE 1
+#define CONFIG_INT_WDT 1
+#define CONFIG_BTDM_CONTROLLER_BLE_MAX_CONN 3
+#define CONFIG_MBEDTLS_SSL_PROTO_TLS1 1
+#define CONFIG_ESP_GRATUITOUS_ARP 1
+#define CONFIG_AWS_IOT_SHADOW_MAX_SIZE_OF_UNIQUE_CLIENT_ID_BYTES 80
+#define CONFIG_MBEDTLS_ECDSA_C 1
+#define CONFIG_ESPTOOLPY_FLASHFREQ_40M 1
+#define CONFIG_LOG_BOOTLOADER_LEVEL_INFO 1
+#define CONFIG_ESPTOOLPY_FLASHSIZE_2MB 1
+#define CONFIG_HTTPD_MAX_REQ_HDR_LEN 512
+#define CONFIG_BTDM_CONTROLLER_PINNED_TO_CORE 0
+#define CONFIG_AWS_IOT_MQTT_PORT 8883
+#define CONFIG_FREERTOS_THREAD_LOCAL_STORAGE_POINTERS 1
+#define CONFIG_MBEDTLS_ECDH_C 1
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_ELLIPTIC_CURVE 1
+#define CONFIG_ESP32_WIFI_STATIC_RX_BUFFER_NUM 10
+#define CONFIG_AWS_IOT_MQTT_MAX_RECONNECT_WAIT_INTERVAL 128000
+#define CONFIG_MBEDTLS_SSL_ALPN 1
+#define CONFIG_BTM_TRACE_LEVEL_WARNING 1
+#define CONFIG_MBEDTLS_PEM_WRITE_C 1
+#define CONFIG_MBEDTLS_SSL_OUT_CONTENT_LEN 4096
+#define CONFIG_RFCOMM_TRACE_LEVEL_WARNING 1
+#define CONFIG_LOG_DEFAULT_LEVEL_INFO 1
+#define CONFIG_BT_RESERVE_DRAM 0xdb5c
+#define CONFIG_FATFS_FS_LOCK 0
+#define CONFIG_IP_LOST_TIMER_INTERVAL 120
+#define CONFIG_SPIFFS_META_LENGTH 4
+#define CONFIG_ESP32_PANIC_PRINT_REBOOT 1
+#define CONFIG_MB_CONTROLLER_NOTIFY_QUEUE_SIZE 20
+#define CONFIG_MBEDTLS_ECP_DP_BP384R1_ENABLED 1
+#define CONFIG_MBEDTLS_ECP_DP_SECP256K1_ENABLED 1
+#define CONFIG_AWS_IOT_MQTT_RX_BUF_LEN 512
+#define CONFIG_MB_SERIAL_BUF_SIZE 256
+#define CONFIG_CONSOLE_UART_BAUDRATE 115200
+#define CONFIG_LWIP_MAX_SOCKETS 10
+#define CONFIG_LWIP_NETIF_LOOPBACK 1
+#define CONFIG_MCA_TRACE_LEVEL_WARNING 1
+#define CONFIG_EMAC_TASK_PRIORITY 20
+#define CONFIG_TIMER_TASK_STACK_DEPTH 2048
+#define CONFIG_TCP_MSS 1436
+#define CONFIG_MBEDTLS_ECP_DP_CURVE25519_ENABLED 1
+#define CONFIG_BTIF_INITIAL_TRACE_LEVEL 2
+#define CONFIG_BTDM_CONTROLLER_BLE_MAX_CONN_EFF 3
+#define CONFIG_FATFS_CODEPAGE 437
+#define CONFIG_APPL_TRACE_LEVEL_WARNING 1
+#define CONFIG_BTC_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ESP32_DEFAULT_CPU_FREQ_160 1
+#define CONFIG_LWIP_MAX_UDP_PCBS 16
+#define CONFIG_ESPTOOLPY_BAUD 115200
+#define CONFIG_INT_WDT_CHECK_CPU1 1
+#define CONFIG_AVRC_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ADC_CAL_LUT_ENABLE 1
+#define CONFIG_AWS_IOT_MQTT_TX_BUF_LEN 512
+#define CONFIG_FLASHMODE_DIO 1
+#define CONFIG_ESPTOOLPY_AFTER_RESET 1
+#define CONFIG_OPTIMIZATION_ASSERTIONS_ENABLED 1
+#define CONFIG_LWIP_DHCPS_MAX_STATION_NUM 8
+#define CONFIG_TOOLPREFIX "xtensa-esp32-elf-"
+#define CONFIG_MBEDTLS_ECP_C 1
+#define CONFIG_FREERTOS_IDLE_TASK_STACKSIZE 1536
+#define CONFIG_MBEDTLS_RC4_DISABLED 1
+#define CONFIG_GAP_TRACE_LEVEL_WARNING 1
+#define CONFIG_CONSOLE_UART_NUM 0
+#define CONFIG_AWS_IOT_SHADOW_MAX_JSON_TOKEN_EXPECTED 120
+#define CONFIG_ESP32_APPTRACE_LOCK_ENABLE 1
+#define CONFIG_PTHREAD_STACK_MIN 768
+#define CONFIG_ESP32_RTC_CLOCK_SOURCE_INTERNAL_RC 1
+#define CONFIG_ESPTOOLPY_BAUD_115200B 1
+#define CONFIG_TCP_OVERSIZE_MSS 1
+#define CONFIG_FOUR_UNIVERSAL_MAC_ADDRESS 1
+#define CONFIG_CONSOLE_UART_DEFAULT 1
+#define CONFIG_NUMBER_OF_UNIVERSAL_MAC_ADDRESS 4
+#define CONFIG_GATT_TRACE_LEVEL_WARNING 1
+#define CONFIG_ESPTOOLPY_FLASHSIZE_DETECT 1
+#define CONFIG_EXAMPLE_EMBEDDED_CERTS 1
+#define CONFIG_TIMER_TASK_STACK_SIZE 3584
+#define CONFIG_BTIF_TRACE_LEVEL_WARNING 1
+#define CONFIG_ESP32_ENABLE_COREDUMP_TO_NONE 1
+#define CONFIG_HCI_INITIAL_TRACE_LEVEL 2
+#define CONFIG_AVDT_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MBEDTLS_X509_CRL_PARSE_C 1
+#define CONFIG_SCAN_DUPLICATE_BY_DEVICE_ADDR 1
+#define CONFIG_AWS_IOT_SHADOW_MAX_SHADOW_TOPIC_LENGTH_WITHOUT_THINGNAME 60
+#define CONFIG_MB_SERIAL_TASK_STACK_SIZE 2048
+#define CONFIG_GATTS_SEND_SERVICE_CHANGE_AUTO 1
+#define CONFIG_LWIP_DHCPS_LEASE_UNIT 60
+#define CONFIG_SPIFFS_USE_MAGIC 1
+#define CONFIG_TCPIP_TASK_STACK_SIZE 3072
+#define CONFIG_BLUFI_TRACE_LEVEL_WARNING 1
+#define CONFIG_BLUEDROID_PINNED_TO_CORE_0 1
+#define CONFIG_TASK_WDT 1
+#define CONFIG_RFCOMM_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MAIN_TASK_STACK_SIZE 3584
+#define CONFIG_SPIFFS_PAGE_CHECK 1
+#define CONFIG_ESP32_WIFI_TASK_PINNED_TO_CORE_0 1
+#define CONFIG_LWIP_MAX_ACTIVE_TCP 16
+#define CONFIG_TASK_WDT_TIMEOUT_S 5
+#define CONFIG_INT_WDT_TIMEOUT_MS 300
+#define CONFIG_ESPTOOLPY_FLASHMODE "dio"
+#define CONFIG_BTC_TASK_STACK_SIZE 3072
+#define CONFIG_BLUEDROID_ENABLED 1
+#define CONFIG_NEWLIB_STDIN_LINE_ENDING_CR 1
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_ECDH_RSA 1
+#define CONFIG_ESPTOOLPY_BEFORE "default_reset"
+#define CONFIG_ADC2_DISABLE_DAC 1
+#define CONFIG_FATFS_LFN_HEAP 1
+#define CONFIG_BLE_ADV_REPORT_FLOW_CONTROL_NUM 100
+#define CONFIG_LOG_DEFAULT_LEVEL 3
+#define CONFIG_FREERTOS_ASSERT_ON_UNTESTED_FUNCTION 1
+#define CONFIG_TIMER_QUEUE_LENGTH 10
+#define CONFIG_SUPPRESS_SELECT_DEBUG_OUTPUT 1
+#define CONFIG_GATTS_SEND_SERVICE_CHANGE_MODE 0
+#define CONFIG_TCPIP_TASK_AFFINITY_NO_AFFINITY 1
+#define CONFIG_MAKE_WARN_UNDEFINED_VARIABLES 1
+#define CONFIG_FATFS_TIMEOUT_MS 10000
+#define CONFIG_ESP32_WIFI_DYNAMIC_RX_BUFFER_NUM 32
+#define CONFIG_ESP_HTTP_CLIENT_ENABLE_HTTPS 1
+#define CONFIG_PAN_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MBEDTLS_CCM_C 1
+#define CONFIG_SPI_MASTER_ISR_IN_IRAM 1
+#define CONFIG_MCA_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ESP32_PHY_MAX_WIFI_TX_POWER 20
+#define CONFIG_A2D_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ESP32_RTC_CLK_CAL_CYCLES 1024
+#define CONFIG_ESP32_WIFI_TX_BA_WIN 6
+#define CONFIG_ESP32_WIFI_NVS_ENABLED 1
+#define CONFIG_MDNS_MAX_SERVICES 10
+#define CONFIG_EMAC_CHECK_LINK_PERIOD_MS 2000
+#define CONFIG_BTDM_LPCLK_SEL_MAIN_XTAL 1
+#define CONFIG_MBEDTLS_ECP_DP_SECP224R1_ENABLED 1
+#define CONFIG_LIBSODIUM_USE_MBEDTLS_SHA 1
+#define CONFIG_AWS_IOT_SDK 1
+#define CONFIG_DMA_RX_BUF_NUM 10
+#define CONFIG_MBEDTLS_ECP_DP_SECP384R1_ENABLED 1
+#define CONFIG_TCP_SYNMAXRTX 6
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA 1
+#define CONFIG_BTDM_CONTROLLER_BR_EDR_MAX_SYNC_CONN_EFF 0
+#define CONFIG_PYTHON "python"
+#define CONFIG_MBEDTLS_ECP_NIST_OPTIM 1
+#define CONFIG_ESP32_TIME_SYSCALL_USE_RTC_FRC1 1
+#define CONFIG_ESPTOOLPY_COMPRESSED 1
+#define CONFIG_PARTITION_TABLE_FILENAME "partitions_singleapp.csv"
+#define CONFIG_MB_CONTROLLER_STACK_SIZE 4096
+#define CONFIG_TCP_SND_BUF_DEFAULT 5744
+#define CONFIG_GARP_TMR_INTERVAL 60
+#define CONFIG_LWIP_DHCP_MAX_NTP_SERVERS 1
+#define CONFIG_BNEP_INITIAL_TRACE_LEVEL 2
+#define CONFIG_HCI_TRACE_LEVEL_WARNING 1
+#define CONFIG_TCP_MSL 60000
+#define CONFIG_MBEDTLS_SSL_PROTO_TLS1_1 1
+#define CONFIG_LWIP_SO_REUSE_RXTOALL 1
+#define CONFIG_MB_CONTROLLER_NOTIFY_TIMEOUT 20
+#define CONFIG_PARTITION_TABLE_SINGLE_APP 1
+#define CONFIG_ESP32_WIFI_RX_BA_WIN 6
+#define CONFIG_MBEDTLS_X509_CSR_PARSE_C 1
+#define CONFIG_SPIFFS_USE_MTIME 1
+#define CONFIG_BTC_TRACE_LEVEL_WARNING 1
+#define CONFIG_EMAC_TASK_STACK_SIZE 3072
+#define CONFIG_SMP_TRACE_LEVEL_WARNING 1
+#define CONFIG_MB_QUEUE_LENGTH 20
+#define CONFIG_SW_COEXIST_PREFERENCE_VALUE 2
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_ECDHE_RSA 1
+#define CONFIG_LWIP_DHCP_DOES_ARP_CHECK 1
+#define CONFIG_FREERTOS_TASK_FUNCTION_WRAPPER 1
+#define CONFIG_SYSTEM_EVENT_TASK_STACK_SIZE 2304
+#define CONFIG_BOOTLOADER_VDDSDIO_BOOST_1_9V 1
+#define CONFIG_A2D_TRACE_LEVEL_WARNING 1
+#define CONFIG_ESP32_DEEP_SLEEP_WAKEUP_DELAY 2000
+#define CONFIG_AWS_IOT_MQTT_NUM_SUBSCRIBE_HANDLERS 5
+#define CONFIG_BROWNOUT_DET_LVL 0
+#define CONFIG_MBEDTLS_PEM_PARSE_C 1
+#define CONFIG_SPIFFS_GC_MAX_RUNS 10
+#define CONFIG_ESP32_APPTRACE_DEST_NONE 1
+#define CONFIG_MBEDTLS_INTERNAL_MEM_ALLOC 1
+#define CONFIG_MBEDTLS_SSL_PROTO_TLS1_2 1
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_DHE_RSA 1
+#define CONFIG_ESP32_WIFI_DYNAMIC_TX_BUFFER_NUM 32
+#define CONFIG_HTTPD_MAX_URI_LEN 512
+#define CONFIG_MBEDTLS_ECP_DP_BP256R1_ENABLED 1
+#define CONFIG_AVCT_TRACE_LEVEL_WARNING 1
+#define CONFIG_MBEDTLS_ECP_DP_SECP224K1_ENABLED 1
+#define CONFIG_TASK_WDT_CHECK_IDLE_TASK_CPU1 1
+#define CONFIG_ESP32_DEFAULT_CPU_FREQ_MHZ 160
+#define CONFIG_MBEDTLS_HARDWARE_AES 1
+#define CONFIG_FREERTOS_HZ 100
+#define CONFIG_LOG_COLORS 1
+#define CONFIG_OSI_TRACE_LEVEL_WARNING 1
+#define CONFIG_ESP32_PHY_CALIBRATION_AND_DATA_STORAGE 1
+#define CONFIG_STACK_CHECK_NONE 1
+#define CONFIG_ADC_CAL_EFUSE_TP_ENABLE 1
+#define CONFIG_BNEP_TRACE_LEVEL_WARNING 1
+#define CONFIG_FREERTOS_ASSERT_FAIL_ABORT 1
+#define CONFIG_BROWNOUT_DET 1
+#define CONFIG_AWS_IOT_SHADOW_MAX_SIMULTANEOUS_THINGNAMES 10
+#define CONFIG_ESP32_XTAL_FREQ 40
+#define CONFIG_OSI_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MONITOR_BAUD_115200B 1
+#define CONFIG_LOG_BOOTLOADER_LEVEL 3
+#define CONFIG_MBEDTLS_TLS_ENABLED 1
+#define CONFIG_LWIP_MAX_RAW_PCBS 16
+#define CONFIG_SMP_ENABLE 1
+#define CONFIG_HID_TRACE_LEVEL_WARNING 1
+#define CONFIG_AVRC_TRACE_LEVEL_WARNING 1
+#define CONFIG_MBEDTLS_SSL_SESSION_TICKETS 1
+#define CONFIG_SPIFFS_MAX_PARTITIONS 3
+#define CONFIG_ESP_ERR_TO_NAME_LOOKUP 1
+#define CONFIG_BTDM_CONTROLLER_PINNED_TO_CORE_0 1
+#define CONFIG_MBEDTLS_SSL_RENEGOTIATION 1
+#define CONFIG_HID_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ESPTOOLPY_BEFORE_RESET 1
+#define CONFIG_MB_EVENT_QUEUE_TIMEOUT 20
+#define CONFIG_ESPTOOLPY_BAUD_OTHER_VAL 115200
+#define CONFIG_AWS_EXAMPLE_CLIENT_ID "myesp32"
+#define CONFIG_SPIFFS_OBJ_NAME_LEN 32
+#define CONFIG_ESP32_PTHREAD_TASK_PRIO_DEFAULT 5
+#define CONFIG_BTDM_CONTROLLER_BR_EDR_MAX_ACL_CONN_EFF 0
+#define CONFIG_PARTITION_TABLE_MD5 1
+#define CONFIG_TCPIP_RECVMBOX_SIZE 32
+#define CONFIG_TCP_MAXRTX 12
+#define CONFIG_BTM_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ESPTOOLPY_AFTER "hard_reset"
+#define CONFIG_TCPIP_TASK_AFFINITY 0x7FFFFFFF
+#define CONFIG_LWIP_SO_REUSE 1
+#define CONFIG_ESP32_XTAL_FREQ_40 1
+#define CONFIG_BTDM_CONTROLLER_MODE_BLE_ONLY 1
+#define CONFIG_DMA_TX_BUF_NUM 10
+#define CONFIG_LWIP_MAX_LISTENING_TCP 16
+#define CONFIG_FREERTOS_INTERRUPT_BACKTRACE 1
+#define CONFIG_WL_SECTOR_SIZE 4096
+#define CONFIG_ESP32_DEBUG_OCDAWARE 1
+#define CONFIG_MQTT_TRANSPORT_WEBSOCKET 1
+#define CONFIG_TIMER_TASK_PRIORITY 1
+#define CONFIG_MBEDTLS_TLS_CLIENT 1
+#define CONFIG_AWS_IOT_MQTT_MIN_RECONNECT_WAIT_INTERVAL 1000
+#define CONFIG_BTDM_CONTROLLER_HCI_MODE_VHCI 1
+#define CONFIG_BT_ENABLED 1
+#define CONFIG_SDP_TRACE_LEVEL_WARNING 1
+#define CONFIG_SW_COEXIST_PREFERENCE_BALANCE 1
+#define CONFIG_MBEDTLS_ECP_DP_SECP256R1_ENABLED 1
+#define CONFIG_MONITOR_BAUD 115200
+#define CONFIG_ESP32_DEBUG_STUBS_ENABLE 1
+#define CONFIG_TCPIP_LWIP 1
+#define CONFIG_REDUCE_PHY_TX_POWER 1
+#define CONFIG_BOOTLOADER_WDT_TIME_MS 9000
+#define CONFIG_PAN_TRACE_LEVEL_WARNING 1
+#define CONFIG_FREERTOS_CORETIMER_0 1
+#define CONFIG_PARTITION_TABLE_CUSTOM_FILENAME "partitions.csv"
+#define CONFIG_MBEDTLS_HAVE_TIME 1
+#define CONFIG_FREERTOS_CHECK_STACKOVERFLOW_CANARY 1
+#define CONFIG_TCP_QUEUE_OOSEQ 1
+#define CONFIG_GATTS_ENABLE 1
+#define CONFIG_ADC_CAL_EFUSE_VREF_ENABLE 1
+#define CONFIG_MBEDTLS_TLS_SERVER 1
+#define CONFIG_MBEDTLS_TLS_SERVER_AND_CLIENT 1
+#define CONFIG_BLE_ADV_REPORT_FLOW_CONTROL_SUPPORTED 1
+#define CONFIG_FREERTOS_ISR_STACKSIZE 1536
+#define CONFIG_SUPPORT_TERMIOS 1
+#define CONFIG_OPENSSL_ASSERT_DO_NOTHING 1
+#define CONFIG_WL_SECTOR_SIZE_4096 1
+#define CONFIG_OPTIMIZATION_LEVEL_DEBUG 1
+#define CONFIG_GATT_INITIAL_TRACE_LEVEL 2
+#define CONFIG_FREERTOS_NO_AFFINITY 0x7FFFFFFF
+#define CONFIG_AWS_IOT_MQTT_HOST ""
+#define CONFIG_L2CAP_TRACE_LEVEL_WARNING 1
+#define CONFIG_ESP32_WIFI_AMPDU_TX_ENABLED 1
+#define CONFIG_MB_TIMER_INDEX 0
+#define CONFIG_SCAN_DUPLICATE_TYPE 0
+#define CONFIG_MBEDTLS_ECP_DP_SECP192R1_ENABLED 1
+#define CONFIG_APPL_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MBEDTLS_ECP_DP_BP512R1_ENABLED 1
+#define CONFIG_SMP_INITIAL_TRACE_LEVEL 2
+#define CONFIG_MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA 1
+#define CONFIG_SPI_SLAVE_ISR_IN_IRAM 1
+#define CONFIG_L2CAP_INITIAL_TRACE_LEVEL 2
+#define CONFIG_SYSTEM_EVENT_QUEUE_SIZE 32
+#define CONFIG_BT_ACL_CONNECTIONS 4
+#define CONFIG_FATFS_MAX_LFN 255
+#define CONFIG_ESP32_WIFI_TX_BUFFER_TYPE 1
+#define CONFIG_BOOTLOADER_WDT_ENABLE 1
+#define CONFIG_GAP_INITIAL_TRACE_LEVEL 2
+#define CONFIG_ESP32_WIFI_AMPDU_RX_ENABLED 1
+#define CONFIG_LWIP_LOOPBACK_MAX_PBUFS 8
+#define CONFIG_MBEDTLS_SSL_IN_CONTENT_LEN 16384
+#define CONFIG_MB_TIMER_GROUP 0
+#define CONFIG_SPI_FLASH_ROM_DRIVER_PATCH 1
+#define CONFIG_MQTT_TRANSPORT_WEBSOCKET_SECURE 1
+#define CONFIG_SPIFFS_PAGE_SIZE 256
+#define CONFIG_MBEDTLS_ECP_DP_SECP192K1_ENABLED 1
+#define CONFIG_TASK_WDT_CHECK_IDLE_TASK_CPU0 1
+#define CONFIG_ESP32_PTHREAD_TASK_STACK_SIZE_DEFAULT 3072
+#define CONFIG_MB_TIMER_PORT_ENABLED 1
+#define CONFIG_DUPLICATE_SCAN_CACHE_SIZE 200
+#define CONFIG_MONITOR_BAUD_OTHER_VAL 115200
+#define CONFIG_NEWLIB_STDOUT_LINE_ENDING_CRLF 1
+#define CONFIG_ESPTOOLPY_PORT "/dev/ttyUSB0"
+#define CONFIG_SPI_FLASH_WRITING_DANGEROUS_REGIONS_ABORTS 1
+#define CONFIG_MBEDTLS_ASYMMETRIC_CONTENT_LEN 1
+#define CONFIG_BLE_ADV_REPORT_DISCARD_THRSHOLD 20
+#define CONFIG_BLUEDROID_PINNED_TO_CORE 0
+#define CONFIG_BTDM_MODEM_SLEEP_MODE_ORIG 1
+#define CONFIG_ESP32_WIFI_IRAM_OPT 1
+#define CONFIG_BLUFI_INITIAL_TRACE_LEVEL 2
+#define CONFIG_FATFS_API_ENCODING_ANSI_OEM 1
diff --git a/examples/espidf-ulp-pulse/src/ulp_example_main.c b/examples/espidf-ulp-pulse/src/ulp_example_main.c
new file mode 100644
index 0000000..a6e76ba
--- /dev/null
+++ b/examples/espidf-ulp-pulse/src/ulp_example_main.c
@@ -0,0 +1,119 @@
+/* ULP Example
+
+   This example code is in the Public Domain (or CC0 licensed, at your option.)
+
+   Unless required by applicable law or agreed to in writing, this
+   software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+   CONDITIONS OF ANY KIND, either express or implied.
+*/
+
+#include <stdio.h>
+#include "esp_sleep.h"
+#include "nvs.h"
+#include "nvs_flash.h"
+#include "soc/rtc_cntl_reg.h"
+#include "soc/sens_reg.h"
+#include "soc/rtc_periph.h"
+#include "driver/gpio.h"
+#include "driver/rtc_io.h"
+#include "esp32/ulp.h"
+#include "ulp_main.h"
+
+extern const uint8_t ulp_main_bin_start[] asm("_binary_ulp_main_bin_start");
+extern const uint8_t ulp_main_bin_end[]   asm("_binary_ulp_main_bin_end");
+
+static void init_ulp_program();
+static void update_pulse_count();
+
+void app_main()
+{
+    esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
+    if (cause != ESP_SLEEP_WAKEUP_ULP) {
+        printf("Not ULP wakeup, initializing ULP\n");
+        init_ulp_program();
+    } else {
+        printf("ULP wakeup, saving pulse count\n");
+        update_pulse_count();
+    }
+
+    printf("Entering deep sleep\n\n");
+    ESP_ERROR_CHECK( esp_sleep_enable_ulp_wakeup() );
+    esp_deep_sleep_start();
+}
+
+static void init_ulp_program()
+{
+    esp_err_t err = ulp_load_binary(0, ulp_main_bin_start,
+            (ulp_main_bin_end - ulp_main_bin_start) / sizeof(uint32_t));
+    ESP_ERROR_CHECK(err);
+
+    /* GPIO used for pulse counting. */
+    gpio_num_t gpio_num = GPIO_NUM_0;
+    assert(rtc_gpio_desc[gpio_num].reg && "GPIO used for pulse counting must be an RTC IO");
+
+    /* Initialize some variables used by ULP program.
+     * Each 'ulp_xyz' variable corresponds to 'xyz' variable in the ULP program.
+     * These variables are declared in an auto generated header file,
+     * 'ulp_main.h', name of this file is defined in component.mk as ULP_APP_NAME.
+     * These variables are located in RTC_SLOW_MEM and can be accessed both by the
+     * ULP and the main CPUs.
+     *
+     * Note that the ULP reads only the lower 16 bits of these variables.
+     */
+    ulp_debounce_counter = 3;
+    ulp_debounce_max_count = 3;
+    ulp_next_edge = 0;
+    ulp_io_number = rtc_gpio_desc[gpio_num].rtc_num; /* map from GPIO# to RTC_IO# */
+    ulp_edge_count_to_wake_up = 10;
+
+    /* Initialize selected GPIO as RTC IO, enable input, disable pullup and pulldown */
+    rtc_gpio_init(gpio_num);
+    rtc_gpio_set_direction(gpio_num, RTC_GPIO_MODE_INPUT_ONLY);
+    rtc_gpio_pulldown_dis(gpio_num);
+    rtc_gpio_pullup_dis(gpio_num);
+    rtc_gpio_hold_en(gpio_num);
+
+    /* Disconnect GPIO12 and GPIO15 to remove current drain through
+     * pullup/pulldown resistors.
+     * GPIO12 may be pulled high to select flash voltage.
+     */
+    rtc_gpio_isolate(GPIO_NUM_12);
+    rtc_gpio_isolate(GPIO_NUM_15);
+    esp_deep_sleep_disable_rom_logging(); // suppress boot messages
+
+    /* Set ULP wake up period to T = 20ms.
+     * Minimum pulse width has to be T * (ulp_debounce_counter + 1) = 80ms.
+     */
+    ulp_set_wakeup_period(0, 20000);
+
+    /* Start the program */
+    err = ulp_run(&ulp_entry - RTC_SLOW_MEM);
+    ESP_ERROR_CHECK(err);
+}
+
+static void update_pulse_count()
+{
+    const char* namespace = "plusecnt";
+    const char* count_key = "count";
+
+    ESP_ERROR_CHECK( nvs_flash_init() );
+    nvs_handle handle;
+    ESP_ERROR_CHECK( nvs_open(namespace, NVS_READWRITE, &handle));
+    uint32_t pulse_count = 0;
+    esp_err_t err = nvs_get_u32(handle, count_key, &pulse_count);
+    assert(err == ESP_OK || err == ESP_ERR_NVS_NOT_FOUND);
+    printf("Read pulse count from NVS: %5d\n", pulse_count);
+
+    /* ULP program counts signal edges, convert that to the number of pulses */
+    uint32_t pulse_count_from_ulp = (ulp_edge_count & UINT16_MAX) / 2;
+    /* In case of an odd number of edges, keep one until next time */
+    ulp_edge_count = ulp_edge_count % 2;
+    printf("Pulse count from ULP: %5d\n", pulse_count_from_ulp);
+
+    /* Save the new pulse count to NVS */
+    pulse_count += pulse_count_from_ulp;
+    ESP_ERROR_CHECK(nvs_set_u32(handle, count_key, pulse_count));
+    ESP_ERROR_CHECK(nvs_commit(handle));
+    nvs_close(handle);
+    printf("Wrote updated pulse count to NVS: %5d\n", pulse_count);
+}
diff --git a/examples/espidf-ulp-pulse/test/README b/examples/espidf-ulp-pulse/test/README
new file mode 100644
index 0000000..df5066e
--- /dev/null
+++ b/examples/espidf-ulp-pulse/test/README
@@ -0,0 +1,11 @@
+
+This directory is intended for PIO Unit Testing and project tests.
+
+Unit Testing is a software testing method by which individual units of
+source code, sets of one or more MCU program modules together with associated
+control data, usage procedures, and operating procedures, are tested to
+determine whether they are fit for use. Unit testing finds problems early
+in the development cycle.
+
+More information about PIO Unit Testing:
+- https://docs.platformio.org/page/plus/unit-testing.html
diff --git a/examples/espidf-ulp-pulse/ulp/pulse_cnt.S b/examples/espidf-ulp-pulse/ulp/pulse_cnt.S
new file mode 100644
index 0000000..774375e
--- /dev/null
+++ b/examples/espidf-ulp-pulse/ulp/pulse_cnt.S
@@ -0,0 +1,157 @@
+/* ULP Example: pulse counting
+
+   This example code is in the Public Domain (or CC0 licensed, at your option.)
+
+   Unless required by applicable law or agreed to in writing, this
+   software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+   CONDITIONS OF ANY KIND, either express or implied.
+
+   This file contains assembly code which runs on the ULP.
+
+   ULP wakes up to run this code at a certain period, determined by the values
+   in SENS_ULP_CP_SLEEP_CYCx_REG registers. On each wake up, the program checks
+   the input on GPIO0. If the value is different from the previous one, the
+   program "debounces" the input: on the next debounce_max_count wake ups,
+   it expects to see the same value of input.
+   If this condition holds true, the program increments edge_count and starts
+   waiting for input signal polarity to change again.
+   When the edge counter reaches certain value (set by the main program),
+   this program running triggers a wake up from deep sleep.
+*/
+
+/* ULP assembly files are passed through C preprocessor first, so include directives
+   and C macros may be used in these files 
+ */
+#include "soc/rtc_cntl_reg.h"
+#include "soc/rtc_io_reg.h"
+#include "soc/soc_ulp.h"
+
+	/* Define variables, which go into .bss section (zero-initialized data) */
+	.bss
+	/* Next input signal edge expected: 0 (negative) or 1 (positive) */
+	.global next_edge
+next_edge:
+	.long 0
+
+	/* Counter started when signal value changes.
+	   Edge is "debounced" when the counter reaches zero. */
+	.global debounce_counter
+debounce_counter:
+	.long 0
+
+	/* Value to which debounce_counter gets reset.
+	   Set by the main program. */
+	.global debounce_max_count
+debounce_max_count:
+	.long 0
+
+	/* Total number of signal edges acquired */
+	.global edge_count
+edge_count:
+	.long 0
+
+	/* Number of edges to acquire before waking up the SoC.
+	   Set by the main program. */
+	.global edge_count_to_wake_up
+edge_count_to_wake_up:
+	.long 0
+
+	/* RTC IO number used to sample the input signal.
+	   Set by main program. */
+	.global io_number
+io_number:
+	.long 0
+
+	/* Code goes into .text section */
+	.text
+	.global entry
+entry:
+	/* Load io_number */
+	move r3, io_number
+	ld r3, r3, 0
+
+	/* Lower 16 IOs and higher need to be handled separately,
+	 * because r0-r3 registers are 16 bit wide.
+	 * Check which IO this is.
+	 */
+	move r0, r3
+	jumpr read_io_high, 16, ge
+
+	/* Read the value of lower 16 RTC IOs into R0 */
+	READ_RTC_REG(RTC_GPIO_IN_REG, RTC_GPIO_IN_NEXT_S, 16)
+	rsh r0, r0, r3
+	jump read_done
+
+	/* Read the value of RTC IOs 16-17, into R0 */
+read_io_high:
+	READ_RTC_REG(RTC_GPIO_IN_REG, RTC_GPIO_IN_NEXT_S + 16, 2)
+	sub r3, r3, 16
+	rsh r0, r0, r3
+
+read_done:
+	and r0, r0, 1
+	/* State of input changed? */
+	move r3, next_edge
+	ld r3, r3, 0
+	add r3, r0, r3
+	and r3, r3, 1
+	jump changed, eq
+	/* Not changed */
+	/* Reset debounce_counter to debounce_max_count */
+	move r3, debounce_max_count
+	move r2, debounce_counter
+	ld r3, r3, 0
+	st r3, r2, 0
+	/* End program */
+	halt
+
+	.global changed
+changed:
+	/* Input state changed */
+	/* Has debounce_counter reached zero? */
+	move r3, debounce_counter
+	ld r2, r3, 0
+	add r2, r2, 0 /* dummy ADD to use "jump if ALU result is zero" */
+	jump edge_detected, eq
+	/* Not yet. Decrement debounce_counter */
+	sub r2, r2, 1
+	st r2, r3, 0
+	/* End program */
+	halt
+
+	.global edge_detected
+edge_detected:
+	/* Reset debounce_counter to debounce_max_count */
+	move r3, debounce_max_count
+	move r2, debounce_counter
+	ld r3, r3, 0
+	st r3, r2, 0
+	/* Flip next_edge */
+	move r3, next_edge
+	ld r2, r3, 0
+	add r2, r2, 1
+	and r2, r2, 1
+	st r2, r3, 0
+	/* Increment edge_count */
+	move r3, edge_count
+	ld r2, r3, 0
+	add r2, r2, 1
+	st r2, r3, 0
+	/* Compare edge_count to edge_count_to_wake_up */
+	move r3, edge_count_to_wake_up
+	ld r3, r3, 0
+	sub r3, r3, r2
+	jump wake_up, eq
+	/* Not yet. End program */
+	halt
+
+	.global wake_up
+wake_up:
+	/* Check if the system can be woken up */
+	READ_RTC_FIELD(RTC_CNTL_LOW_POWER_ST_REG, RTC_CNTL_RDY_FOR_WAKEUP)
+	and r0, r0, 1
+	jump wake_up, eq
+
+	/* Wake up the SoC, end program */
+	wake
+	halt
diff --git a/platform.json b/platform.json
index 29ebc37..199749d 100644
--- a/platform.json
+++ b/platform.json
@@ -42,6 +42,11 @@
       "type": "toolchain",
       "version": "~2.50200.0"
     },
+    "toolchain-esp32ulp": {
+      "type": "toolchain",
+      "optional": true,
+      "version": "~1.22851.190618"
+    },
     "framework-arduinoespressif32": {
       "type": "framework",
       "optional": true,
diff --git a/platform.py b/platform.py
index 088a5fe..e2ecbbe 100644
--- a/platform.py
+++ b/platform.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from os.path import isdir
+
 from platformio.managers.platform import PlatformBase
 
 
@@ -22,6 +24,9 @@ class Espressif32Platform(PlatformBase):
             self.packages['tool-mkspiffs']['optional'] = False
         if variables.get("upload_protocol"):
             self.packages['tool-openocd-esp32']['optional'] = False
+        if isdir("ulp"):
+            self.packages['toolchain-esp32ulp']['optional'] = False
+
         return PlatformBase.configure_default_packages(self, variables,
                                                        targets)