arduino-abstract-serial

Abstract serial class for all the various HardwareSerial, SoftwareSerial, SerialUSB, etc. so that they can be easily passed by reference into a function

This library is intended to provide a Serial class that wraps around the various UART, USBSerial, and other interesting serial ports seen in the Arduino ecosystem. This is done by creating an API-compliant child class to this abstract class. This child class can be passed in to a function or library in abstract, so the program does not have to maintain its own wrapper code to make multiple types of serial port work.

This base library will include code to abstract a few different serial ports and other stream-like devices that need to be accessed beyond their stream- like capabilities. Basically, this library's functions wrap the actual serial port's functions one-to-one. In cases where functionality is not available, like SoftwareSerial's availableForWrite and Teensy's USB Serial port's begin, this library will return a constant.

This class was based on the public interface of HardwareSerial. If there are any gaping incompatibilities with other kinds of ports, please open an issue on GitHub! https://github.com/computergeek125/arduino-abstract-serial

How it works

AbstractSerial is the root class. Like other Serial ports in Arduino, it inherits from Stream. It defines a common interface for serial ports. The other files inherit from it, and wrap the actual serial port being used. When using these in a function or class, pass the child object as a reference of type AbsSer. See ./examples/ in this repo for examples.

Things to know

Most hardware serial ports behave similarly. But in the case of some direct USB serial ports, there are some functions that aren't used. In the case of SoftwareSerial, availableForWrite and begin(unsigned long baud, uint8_t config) do not exist.

In these cases where it is functionality that most other serial ports use, the library masks this. SoftwareSerial's availableForWrite always returns 0 as data is transmitted synchronously. In the case of the Teensy's Serial, which points to a special USB port, the begin function in this wrapper returns without modifying the wrapped object.