* Elevate RTC2 interrupt priority to same level as UARTE to prevent
race condition on shared variables.
* Remove unused TXDRDY event code.
* Fix typo in macro.
It has been noticed that there is a problem with us ticker on NRF_52840 board after 32 bit counter has been used for us ticker on NRF52 family boards.
Currently NRF52 symbol is defined only for MCU_NRF52832 (not for MCU_NRF52840) and based on this symbol 16 or 32 bit counter is selected (16 bit for NRF51 family and 32 for NRF52 family).
Since MCU_NRF52840 defines NRF52840_XXAA and provides 32 bit counters, 32 bit counter should be selected also when NRF52840_XXAA symbol is defined.
New changes to Mbed error reporting in 5.9 exposed bug in SPI
driver where an instance was uninitialized twice which triggered
an ASSERT.
This fix keeps track of which instance has been initialized and
only calls uninit when it is safe.
Set the second highest user level, leaving the highest for UART (we are having constant overflows) and two levels below for everything else.
This should increase the timer accuracy.
RTC counter is 24-bit. Upper layer handles counter size and wraps ticks count when interrupt is to be fired before passing it to common_rtc_set_interrupt(), but for consistency and safety reasons we can wrap it again in the NRF driver.
The nrf section features has different implementations for each compilers supported by mbed-os. The header guard was ruling out compiler other than GCC by checking if __GNUC__ is defined. This check is not applicable on mbed os as the ARM compiler compile sources with gnu compatibility.
This patch makes sure that the right implementation is selected for the right compiler . The previous patch has been reverted as it is not reliable.
I decided to move these files to the targets/TARGET_NORDIC/TARGET_NRF5x/TARGET_NRF51 since us_ticker.h is for sure specific for NRF51_DK and common_rtc.c might be valid also for NRF52, but this needs to be checked while porting NRF52_DK board.
Provide the following modifications for lp ticker driver:
- According to NRF51_DK reference manual rtc interrupt cannot be controlled by rtc event. In the previous implementation interrupts were enabled permanently and specific interrupt was enabled/disabled by enabling/disabling the specific event. If event is enabled, then event signal is provided to Programmable Peripheral Interconnect (PPI). If interrupt is enabled, then interrupt signal is provided to Nested Vector Interrupt Controller (NVIC). Disable all events permanently. Enable lp ticker overflow interrupt permanently(needed for RTC), disable lp ticker capture/compare interrupt on init (lp_ticker_init) , enable lp ticker interrupt when lp ticker interrupt is set (lp_ticker_set_interrupt), disable lp ticker interrupt on disable request(lp_ticker_disable_interrupt).
- Provide lp ticker data for higher level (freq: 32kHz / len: 24 bits),
- Add the following features to init routine: disable lp ticker interrupt.
- Make ticker driver to operate on ticks instead of us.
- Simplify lp ticker read and set interrupt routines (upper layers handle conversion to us and interrupt scheduling).
According to new ticker standards the following requirements for us ticker are not met on RRF5 boards:
- has a frequency between 250KHz and 8MHz (currently is driven by 32kHz clock)
- ticker increments by 1 each tick (currently is scaled to 1 MHz by incrementing counter by ~31)
Since BLE softdevice uses TIMER0 the proposition is to use high speed TIMER1 for us ticker configured as follows:
- TIMER counter width: 16 bits (max)
- TIMER frequency: 1MHz
This solution also uses Timer's capture/compare register 0 to specify interrupt time and Timer's capture/compare register 1 to read current timer value.
Marcus Chang
Martin Kojtal
Przemyslaw Stekiel
Cruz Monrreal
Bernhard Schuster
Melvin van den berg
Vincent Coubard
Anna Bridge
Andrew Leech
Bartek Szatkowski
Steven Cartmell