Make `upload.port.*` properties available in compile patterns

[Ebola-Chan-bot]

Describe the request

This issue has already been raised in the forum, but my application scenario is slightly different from his. My computer is connected to multiple boards on different COM ports. They have basically the same model and program to run, but the devices they operate are plugged into different pins.

I would like to have a compile-time macro definition that indicates the COM port currently selected by the IDE. For example, if I had a compile-time attached macro definition "COM", I could code:

#define Pin constexpr uint8_t
#if COM == 3
Pin pBlueLed = 11;
Pin pActiveBuzzer = 52;
#elif COM == 4
Pin pBlueLed = 8;
Pin pActiveBuzzer = 22;
#elif COM == 5
Pin pBlueLed = 11;
Pin pActiveBuzzer = 22;
#endif

This way I don't need to change the pin number every time to upload to a different COM port. I can write the corresponding pin numbers of all COM ports, and then the compiler preprocessing automatically selects the correct pin configuration.

Describe the current behavior

There currently seems to be no way to get COM numbers in the code.

Arduino IDE version

2.2.1

Operating system

Windows

Operating system version

10

Additional context

No response

Issue checklist

• I searched for previous requests in the issue tracker
• I verified the feature was still missing when using the latest nightly build
• My request contains all necessary details

[per1234]

Hi @silver-fang. I transferred this to the issue tracker for Arduino CLI because it is Arduino CLI that provides the sketch compilation capability to Arduino IDE under the hood.

Arduino's approach to the boards platform system is to provide a powerful and flexible framework and give the platform developers the freedom to choose what to build on that framework.

So hardcoding such a macro into the platform framework would be a terrible idea. Instead what would be done is to make the port selection data available via platform properties. The platform developer can then add a -D flag to the compilation command patterns to set the macro (e.g., -DARDUINO_UPLOAD_PORT_ADDRESS="{upload.port.address}").

In fact the platform frame work already provides such properties:

https://arduino.github.io/arduino-cli/dev/platform-specification/#serial-port

However, those properties are only available for use in the upload-related command patterns.

Arduino CLI separates the compilation and upload operations. The port is only specified during the upload operation (e.g., arduino-cli upload --port COM42 ...). The user can specify port data during a compilation operation in order to support the --upload flag, which causes a sequence of compilation+upload similar to how an upload is performed when using Arduino IDE (even though Arduino IDE actually runs two separate commands in sequence).

[cmaglie]

I don't think upload.port.* should be part of the build properties because the compile should not depend on such information. There are many reasons:

• you may want to be able to compile a sketch without having the board at hand
• serial ports have different names on different OS (Windows uses COM1, Linux uses /dev/ttyACM0 or /dev/ttyUSB0, Macos /dev/tty.usb1234 or /dev/cu.usbmodem0, etc.)
• if you disconnect and reconnect a board it may change port...
• you may upload a sketch via Network (then the port is not a COMx but an IP address)
• you may want to use a programmer (so the port is the port of the programmer not of the board)

IMHO you should use a different method to configure the build because the COM port is too ephemeral, you may use an EEPROM (internal or external) to store the board ID or a dip-switch.