Currently port usage is hard-coded to the default port layout, cli
commands are coming in a future commit.
This decouples all code from the global 'serialPorts' structure which
has been removed. Any code that needs to use a serial port can use
findOpenSerialPort() and openSerialPort() and maintain it's own
reference to the port.
Ports can switch between functions. e.g. by default
cli/msp/telemetry/gps
passthrough all use USART1. Each port maintains it's current function.
see begin/endSerialPortFunction.
There are only certain combinations of serial port functions that are
supported, these are listed in serialPortFunctionScenario_e.
This commit also adds a few 'static' keywords to variables that should
have been.
There a a few other minor fixes and tweaks to various bits of code that
this uncovered too.
TIM8 correctly. Software serial conficted with parallel PWM input. Fixed
crash due to incorrect timerConfig index calculation code.
The crash occurred when capture compare interrupt handlers attempted to
call an invalid callback.
Note: the crash does not affect existing baseflight code since the
formula is OK when using a 2 dimensional array with equal dimensions.
Formula details here:
https://docs.google.com/spreadsheets/d/1UuxnC0VKiprvt1wt3KXffefEWJUb_-ILFLQuP377Anw
