Added a baud argument for (Raw)Serial objects

[bogdanm]

This commit adds a baud argument for Serial and RawSerial objects:

• there is a new Serial constructor with a mandatory baud rate
  argument. The old constructor also got a baud argument with a
  default value (to keep backward compatibility).
• the RawSerial constructor also got a baud argument with a default
  value.

There's also a new configuration parameter (default-serial-baud-rate)
that can be used to specify the default value of the above baud
arguments.

[bogdanm]

@mbed-bot: TEST

HOST_OSES=ALL
BUILD_TOOLCHAINS=GCC_ARM
TARGETS=K64F,NRF51_DK,NRF51_MICROBIT,NUCLEO_F411RE

[bogdanm]

/morph test

[bogdanm]

@0xc0170 @sg-

[mbed-bot]

[Build ${MBED_BUILD_ID}]
FAILURE: Something went wrong when building and testing.

[bogdanm]

@mbed-bot: TEST

HOST_OSES=ALL
BUILD_TOOLCHAINS=GCC_ARM
TARGETS=K64F,NRF51_DK,NRF51_MICROBIT,NUCLEO_F411RE

[mbed-bot]

[Build 798]
FAILURE: Something went wrong when building and testing.

[bogdanm]

This failed because of configuration data issues, again. PR coming up.

[bogdanm]

Will progress once #2423 is merged.

[bogdanm]

@mbed-bot: TEST

HOST_OSES=ALL
BUILD_TOOLCHAINS=GCC_ARM
TARGETS=K64F,NRF51_DK,NRF51_MICROBIT,NUCLEO_F411RE

[bogdanm]

/morph test

[mbed-bot]

[Build 800]
FAILURE: Something went wrong when building and testing.

[bridadan]

@mbed-bot: TEST

HOST_OSES=windows
BUILD_TOOLCHAINS=GCC_ARM
TARGETS=K64F,NRF51_DK,NRF51_MICROBIT,NUCLEO_F411RE

[bridadan]

You should be added now @bogdanm to the morph bot, sorry about that.

/morph test

[mbed-bot]

[Build 801]
FAILURE: Something went wrong when building and testing.

[bogdanm]

Thanks @bridadan.
The failures in this PR are actually config system failures. I'll open a separate issue to discuss this, since it's quite interesting. But anyway, please don't merge yet.

[mbed-bot]

Result: FAILURE

Your command has finished executing! Here's what you wrote!

/morph test

Output

mbed Build Number: 632

Build failed!

[sg-]

@bogdanm Are the issues with config resolved? If not can this be updated to just use 9600 as default?

[bogdanm]

@sg- I've rebased this PR and force-pushed the changes. Let's see if the CI still complains about it.

[bogdanm]

The failure from https://travis-ci.org/ARMmbed/mbed-os/builds/163444683 is very likely related to some limitations in make.py, not to the code in this PR. @bridadan, do you have any advice on how to fix this?

[bridadan]

@bogdanm Can you be a little more specific on what you mean by "limitations"? It looks like the config parameter isn't being declared as a macro correctly.

[bogdanm]

@bridadan True, but only when invoking make.py. build.py seems to work without issues.

[bridadan]

It's possible that the config isn't propagating correctly because that particular line travis is testing uses some of the old ways of compiling mbed 2 tests. You should be able to reproduce the failure fairly easily locally: python tools/make.py -m LPC1768 -t GCC_ARM -c --silent -n MBED_2,MBED_10,MBED_11,MBED_15,MBED_16,MBED_17

[bogdanm]

@bridadan That's the limitation that I'm talking about. The problem isn't reproducing the failure locally, but rather that I'm getting an error from the CI when the code is actually correct.

[bridadan]

@bogdanm Gotcha, thanks for clarifying. I'd have to take a look at what exactly isn't being passed along. Not sure if I'll get to it today but I'll add it to my list. I have a feeling the culprit lies in the call to build_project.

[bridadan]

@bogdanm I think I found the cause of the issue: #2868

Need to get some feedback first though before it gets merged!

[bogdanm]

Rebased again.

[bogdanm]

@bridadan, the CI shows the same error, although now I can see the configuration file in .build/mbed/TARGET_K64F/mbed_lib.json. Maybe it's copied too late?

[bridadan]

@bogdanm I think the actual issue is that the mbed_lib.json that contains the RawSerial config is living in the platform "library" now instead of core. So the macro name is now MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE instead of MBED_CONF_CORE_DEFAULT_SERIAL_BAUD_RATE.

[bogdanm]

Ah thanks, I didn't realize that we changed the name of the library. Fixed.

[bridadan]

/morph test

[mbed-bot]

Result: SUCCESS

Your command has finished executing! Here's what you wrote!

/morph test

Output

mbed Build Number: 1039

All builds and test passed!