Compiling the library

Compiling

The library can be built in IDE managed mode or using the built-in CMake support. Using CMake is highly recommended. More on that Compiling the library.

CMake managed building

1. Add the flexPTP directory to the CMake project as a subdirectory.
2. Either pick a hardware port from pre-made ones (H743_LWIP, H743_ETHERLIB, F407_ETHERLIB, TM4C1294_LWIP) by setting the FLEXPTP_HWPORT CMake variable, or populate the FLEXPTP_HWPORT_SRC with the list of custom hardware port files. Bundled hardware ports can be automatically tailored to some compatible devices by specifying the MCU type (e.g. the STM32F407 port works with the STM32F439 device as well, so that setting FLEXPTP_HWPORT to F439_{LWIP|ETHERLIB}} makes flexPTP using the former port files).
3. Set the FLEXPTP_NSD to the Network Stack Driver files and the FLEXPTP_NETWORK_STACK to the name of the network library or pick from the predefined set (LWIP, ETHERLIB). In the latter case, do not populate FLEXPTP_NETWORK_STACK.
4. Optionally select a predefined Clock servo algoritm (currently only PID is bundled) by setting the FLEXPTP_SERVO variable. If a custom servo is used, and the developer wants the servo to get compiled into the flexPTP library, then populate the FLEXPTP_SERVO_SRC variable with the list of custom servo files. Leaving both FLEXPTP_SERVO and FLEXPTP_SERVO_SRC variables empty results in a warning message during CMake configuration, however it does not necessarily results in a faulty operation. If servo functions are set correctly in the flexptp_options.h configuration file, then the linker will connect flexPTP and the custom servo.
5. Place a completed flexptp_options.h onto a location that is accessible for the flexPTP module. Set the FLEXPTP_INCLUDES CMake variable so that the former requirement is satisfied.
6. Optionally, set FLEXPTP_CPU_PARAMS and FLEXPTP_COMPILE_DEFS to pass target CPU parameters and C definitions.

Building this way results in a static library (libflexptp) that is managed by CMake. This library must be linked to the project's output. Optionally, the name of the output can be suffixed by a tag for reasons by setting the FLEXPTP_TARGET_TAG.

For more information about flexPTP's CMake variables, see CMakeLists.txt.

Example configuration:

The following configuration instructs the flexPTP to:

• use the bundled STM32F407 hardware port with lwIP bindings
• load the bundled lwIP network stack driver (and link against the lwipcore library)
• select the bundled PID controller as the clock servo

set(FLEXPTP_HWPORT "F407_LWIP")
set(FLEXPTP_NSD "LWIP")
set(FLEXPTP_SERVO "PID")

The CMake configuration output will be the following:

[cmake] flexPTP: 'F407_LWIP' hardware port selected
[cmake] flexPTP: 'LWIP' network stack driver selected
[cmake] flexPTP: 'PID' clock servo selected
[cmake] flexPTP: linking against 'lwipcore' network library

IDE managed or manual building

1. Register all *.c and *.h files in the root folder as source file. Do NOT include the hw_port directory!
2. Add the hardware port files if necessary. If a decision was made to pick one of packaged hardware ports, then add ONLY one pair of ptp_port_XXXX.c/h files from the hw_port port directory to the buildset. Repeat the former method for the Network Stack Driver, the network stack library and for the Clock Servo.
3. Place a completed flexptp_options.h onto a location that is accessible for the compiler through the include path.

This way the compilation target is determined by the build system. The build system's settings determine whether a static library is built or the flexPTP will be included into the project's output executable directly.

Precompiled library

It is possible to build flexPTP separately as well. This way only header files and a precompiled library must be added to the project.