With this change, the heap section occupy the whole space from the end of
the bss section to the start of the stack section instead of taking a
fixed size in RAM.
This change allows applications to make a more efficient use of the RAM
available and allows application to be compiled if the space between end
of bss and start of stack is less than 2048 bytes.
Following cube update, there has been changes in cube HAL that impact
the serial_api.c layer. The global state has been moved to separate
global/tx and rx states, so we can now differentiate both.
The NRF51 doesn't have a systick. When the MCU doesn't have a systick, the
HAL has to export several functions which will be use by the kernel to
manage the tick:
* os_tick_init provides the initialization function for the alternative
hardware timer.
* os_tick_val returns the current value of the alternative hardware timer.
* os_tick_ovf returns the overflow flag of the alternative hardware timer.
* os_tick_irqack is an interrupt acknowledge function that is called to
confirm the alternative hardware timer interrupt.
The HAL should also call OS_Tick_Handler needs to be called as the
hardware timer interrupt function.
In the case of the NRF51, two RTCs are available:
* RTC0: reserved for soft device
* RTC1: used by us_ticker.
RTC1 is a 4 channels timers, channel 0 is used for us_ticker, and
in this port channel 1 is used for tick generation.
Implementation notes:
* RTC1_IRQHandler: has to be written in assembly otherwise a stack
overflow will occur because the function OS_Tick_Handler never
returns. This function is called when RTC1 channel IRQ is triggered.
* tick generation has been optimised for a tick with a duration of
1000us.
* us_ticker can still be compiled and used without RTX enabled.
More information about alternative timer as RTX Kernel Timer:
https://www.keil.com/pack/doc/CMSIS/RTX/html/_timer_tick.html
We're ensuring target and host start-up sync here in 2 ways:
1) adding a delay on host side to make sure the serial
initialization can happen before sending a character is sent to target
2) in case of serial_nc_rx_auto.py test, we're sending a
first character S which will trigger the move from rx+tx
to NC+rx.
This should avoid any crossing case due to HSOT being faster than target or vice-versa
During initialization phase of the 2 NC serial tests,
there is a character being sent from host to target,
based on MBED_HOSTTEST_START. The problem is that
the target firmware then creates a "new" serial on the
same serial interface. the new or should, or at least may,
induce a reset of the IP, so that the character sent by host
would be lost. So we're moving the new earlier.
the real testing part happens later, to check the next
character is not received or sent.
Add lock functions so that malloc and environment variable access are
thread safe. Add the compiler option "-o thread-safe" to use the full
version of newlib which is thread safe.
Note that this patch does NOT make file access thread safe.
Vincent Coubard
Martin Kojtal
Jimmy Brisson
Michel Jaouen
Erwan GOURIOU
Laurent Meunier
Bartosz Szczepanski
svastm
Steven Cooreman
Christopher Haster
Anders Lindvall
Russ Butler