this avoids an issue with the ChibiOS 20.3 virtual timer
implementation that can result in a scheduling slip equal to the
system timer period.
Andy has been suggesting this change for a while. I resisted it as I
thought it would impact on soft-serial parsing, but it turns out it
doesn't.
Fixes issue #18383
refactor rcout into separate thread and process all dshot requests there
move uart DMA completion to event model
process dshot locks in strick reverse order when unlocking
convert Shared_DMA to use mutexes
move UART transmit to a thread-per-uart
do blocking UART DMA transactions
do blocking dshot DMA transactions
trim stack sizes
cancel dma transactions on dshot when timeout occurs
support contention stats on blocking locking
move thread supression into chibios_hwdef.py
invalidate DMA bounce buffer correctly
separate UART initialisation into two halves
cleanup UART transaction timeouts
add @SYS/uarts.txt
move half-duplex handling to TX thread
correct thread statistics after use of ExpandingString
set unbuffered TX thread priority owner + 1
correctly unlock serial_led_send()
don't share IMU RX on KakuteF7Mini
observe dshot pulse time more accurately.
set TRBUFF bit for UART DMA transfers
deal with UART DMA timeouts correctly
don't deadlock on reverse ordered DMA locks
change PORT_INT_REQUIRED_STACK to 128
this uses the ChibiOS system timer instead of a separate GPT timer for
the core ChibiOS timer. The advantage is it saves us a timer, plus it
changes ChibiOS to use a 1MHz clock on its timer, which gives us
higher resolution for delays.
This has a remarkable effect on timing jitter, reducing it greatly
Andrew Tridgell
Andy Piper
Siddharth Purohit