Currently implemented only for LPC1768. On this platform, when hardware
flow control is not directly supported, it will be emulated.
Also added "not_implemented.c" as a placeholder for various HAL functions
that might not be implemented on all platforms (in this particular case,
serial_set_flow_control). These are weak implementations that default to a
"not implemented" error message.
The new RawSerial class is a simple wrapper over the serial HAL that can
be safely used from an interrupt handler.
Interrupt chaining code was removed from InterruptIn, Serial and Ticker
because it caused lots of issues with the RTOS. Interrupt chaining is
still possible using the InterruptManager class.
DEVICE_STDIO_MESSAGES is the only #define in device.h that is being used in the library as #ifdef rather than #if. This is misleading since setting it to 0 will not disable including the <stdio.h> libraries.
If the FileBase::lookup operation in the constructor of FilePath returns
NULL, subsequent operations (such as isFile()/isFileSystem()) will call
methods on a NULL 'fb' pointer. This commit fixes this issue by adding
explicit NULL checks and a new method in FilePath (exists()).