This updates the minimal supported version of CMake to 3.16, which in turn enables us to use more CMake features and have a cleaner build system.
This is the version that provides most new features and also the one we use in our latest docker image for CI.
Add TCP port files to provide Modbus TCP interface for communication
Add freemodbus add tcp support for common master/slave iface and tcp example based on socket API
The communication between master and slave checked for each example serial_master, serial_slave (use ModbusPoll TCP)
update tcp example according netif changes, fix ci issues
update TCP slave implementation
update example_test.py to to set IP through stdin
update API documentation
event bit instead of semahore to lock communication resource
update default options and master/slave port files
Closes https://github.com/espressif/esp-idf/issues/858
Closes IDF-452
tout_thr - move calculation and masking into hal layer update driver and uart_ll (add uart_ll_set_rx_tout)
move tout calculation into uart_ll
move calculation of time out in bit time for esp32s2 into low level uart_ll.h file
move uart_hal_get_symb_len() into hal
update set_rx_timeout() to warn user about incorrect value
update HAL, LL 1
fix uart_xx_set_rx_tout() to convert symbol time into bit time
update param description
update tout calculation in LL
update uart_hal_get_max_rx_timeout_thrd() and uart_ll_get_max_rx_timeout_thrd()
add support of modbus master ascii
rename base dir name of master and slave example to be mb_slave, mb_master to avoid conflict with sdio/slave example test
add Kconfig option to enable ASCII and RTU mode separately
update ASCII options + remove cast for errors
added baudrate for examples into Kconfig
updated magic numbers for timer timeout
put ascii private definitions into one file
