+oscillator submodule. ENV preps.

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "pico-hf-oscillator"]
+	path = pico-hf-oscillator
+	url = https://github.com/RPiks/pico-hf-oscillator

CMakeLists.txt

@@ -0,0 +1,61 @@
+# Generated Cmake Pico project file
+
+cmake_minimum_required(VERSION 3.13)
+
+set(CMAKE_BUILD_TYPE "Release") 
+
+set(CMAKE_C_STANDARD 11)
+set(CMAKE_CXX_STANDARD 17)
+
+# Initialise pico_sdk from installed location
+# (note this can come from environment, CMake cache etc)
+# set(PICO_SDK_PATH "/home/jabba/pico-sdk")
+
+set(PICO_BOARD pico CACHE STRING "Board type")
+
+# Pull in Raspberry Pi Pico SDK (must be before project)
+include(pico_sdk_import.cmake)
+
+if (PICO_SDK_VERSION_STRING VERSION_LESS "1.4.0")
+  message(FATAL_ERROR "Raspberry Pi Pico SDK version 1.4.0 (or later) required. Your version is ${PICO_SDK_VERSION_STRING}")
+endif()
+
+project(pico-wspr-tx C CXX ASM)
+
+# Initialise the Raspberry Pi Pico SDK
+pico_sdk_init()
+
+# Add executable. Default name is the project name, version 0.1
+
+add_executable(pico-wspr-tx)
+
+target_sources(pico-wspr-tx PUBLIC
+	             ${CMAKE_CURRENT_LIST_DIR}/pico-hf-oscillator/lib/assert.c
+               ${CMAKE_CURRENT_LIST_DIR}/main.c
+              )
+
+pico_set_program_name(pico-wspr-tx "pico-wspr-tx")
+pico_set_program_version(pico-wspr-tx "0.1")
+
+pico_enable_stdio_uart(pico-wspr-tx 1)
+pico_enable_stdio_usb(pico-wspr-tx 0)
+
+# Add the standard include files to the build
+target_include_directories(pico-wspr-tx PRIVATE
+  ${CMAKE_CURRENT_LIST_DIR}
+  ${CMAKE_CURRENT_LIST_DIR}/.. # for our common lwipopts or any other standard includes, if required
+)
+
+# Add any user requested libraries
+target_link_libraries(
+        pico-wspr-tx
+        pico_stdlib
+        pico_sync
+        pico_multicore
+        hardware_timer
+        hardware_clocks
+        hardware_pio
+        hardware_vreg
+        )
+
+pico_add_extra_outputs(pico-wspr-tx)

build.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+cd build
+cmake ..
+make

clean.sh

@@ -0,0 +1,4 @@
+#!/bin/bash
+
+rm -rf build/*
+

main.c

@@ -0,0 +1,4 @@
+int main()
+{
+
+}

pico-hf-oscillator

@@ -0,0 +1 @@
+Subproject commit 0e5f2086619127d9e8c347dfe67cf1013251c0f2

pico_sdk_import.cmake

@@ -0,0 +1,73 @@
+# This is a copy of <PICO_SDK_PATH>/external/pico_sdk_import.cmake
+
+# This can be dropped into an external project to help locate this SDK
+# It should be include()ed prior to project()
+
+if (DEFINED ENV{PICO_SDK_PATH} AND (NOT PICO_SDK_PATH))
+    set(PICO_SDK_PATH $ENV{PICO_SDK_PATH})
+    message("Using PICO_SDK_PATH from environment ('${PICO_SDK_PATH}')")
+endif ()
+
+if (DEFINED ENV{PICO_SDK_FETCH_FROM_GIT} AND (NOT PICO_SDK_FETCH_FROM_GIT))
+    set(PICO_SDK_FETCH_FROM_GIT $ENV{PICO_SDK_FETCH_FROM_GIT})
+    message("Using PICO_SDK_FETCH_FROM_GIT from environment ('${PICO_SDK_FETCH_FROM_GIT}')")
+endif ()
+
+if (DEFINED ENV{PICO_SDK_FETCH_FROM_GIT_PATH} AND (NOT PICO_SDK_FETCH_FROM_GIT_PATH))
+    set(PICO_SDK_FETCH_FROM_GIT_PATH $ENV{PICO_SDK_FETCH_FROM_GIT_PATH})
+    message("Using PICO_SDK_FETCH_FROM_GIT_PATH from environment ('${PICO_SDK_FETCH_FROM_GIT_PATH}')")
+endif ()
+
+set(PICO_SDK_PATH "${PICO_SDK_PATH}" CACHE PATH "Path to the Raspberry Pi Pico SDK")
+set(PICO_SDK_FETCH_FROM_GIT "${PICO_SDK_FETCH_FROM_GIT}" CACHE BOOL "Set to ON to fetch copy of SDK from git if not otherwise locatable")
+set(PICO_SDK_FETCH_FROM_GIT_PATH "${PICO_SDK_FETCH_FROM_GIT_PATH}" CACHE FILEPATH "location to download SDK")
+
+if (NOT PICO_SDK_PATH)
+    if (PICO_SDK_FETCH_FROM_GIT)
+        include(FetchContent)
+        set(FETCHCONTENT_BASE_DIR_SAVE ${FETCHCONTENT_BASE_DIR})
+        if (PICO_SDK_FETCH_FROM_GIT_PATH)
+            get_filename_component(FETCHCONTENT_BASE_DIR "${PICO_SDK_FETCH_FROM_GIT_PATH}" REALPATH BASE_DIR "${CMAKE_SOURCE_DIR}")
+        endif ()
+        # GIT_SUBMODULES_RECURSE was added in 3.17
+        if (${CMAKE_VERSION} VERSION_GREATER_EQUAL "3.17.0")
+            FetchContent_Declare(
+                    pico_sdk
+                    GIT_REPOSITORY https://github.com/raspberrypi/pico-sdk
+                    GIT_TAG master
+                    GIT_SUBMODULES_RECURSE FALSE
+            )
+        else ()
+            FetchContent_Declare(
+                    pico_sdk
+                    GIT_REPOSITORY https://github.com/raspberrypi/pico-sdk
+                    GIT_TAG master
+            )
+        endif ()
+
+        if (NOT pico_sdk)
+            message("Downloading Raspberry Pi Pico SDK")
+            FetchContent_Populate(pico_sdk)
+            set(PICO_SDK_PATH ${pico_sdk_SOURCE_DIR})
+        endif ()
+        set(FETCHCONTENT_BASE_DIR ${FETCHCONTENT_BASE_DIR_SAVE})
+    else ()
+        message(FATAL_ERROR
+                "SDK location was not specified. Please set PICO_SDK_PATH or set PICO_SDK_FETCH_FROM_GIT to on to fetch from git."
+                )
+    endif ()
+endif ()
+
+get_filename_component(PICO_SDK_PATH "${PICO_SDK_PATH}" REALPATH BASE_DIR "${CMAKE_BINARY_DIR}")
+if (NOT EXISTS ${PICO_SDK_PATH})
+    message(FATAL_ERROR "Directory '${PICO_SDK_PATH}' not found")
+endif ()
+
+set(PICO_SDK_INIT_CMAKE_FILE ${PICO_SDK_PATH}/pico_sdk_init.cmake)
+if (NOT EXISTS ${PICO_SDK_INIT_CMAKE_FILE})
+    message(FATAL_ERROR "Directory '${PICO_SDK_PATH}' does not appear to contain the Raspberry Pi Pico SDK")
+endif ()
+
+set(PICO_SDK_PATH ${PICO_SDK_PATH} CACHE PATH "Path to the Raspberry Pi Pico SDK" FORCE)
+
+include(${PICO_SDK_INIT_CMAKE_FILE})