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
