Arduin-meta.hpp

A metaprogrammed Arduino functions.

Synopsys

#include <Arduino.h>
#include "Arduino-meta.hpp"

constexpr uint8_t LED_RED = 0;
constexpr uint8_t LED_GREEN = 1;
constexpr uint8_t LED_BLUE = 2;

void setup() {
	pinMode(LED_BUILTIN, OUTPUT);

	// static version of pinMode()
	pinMode(
		LED_RED, OUTPUT,
		LED_GREEN, OUTPUT,
		LED_BLUE, OUTPUT
	);
}

void loop() {
	// this is also static
	digitalWrite(LED_RED, HIGH, LED_GREEN, LOW, LED_BLUE, LOW);
	delay(1000);
	digitalWrite(LED_RED, LOW, LED_GREEN, HIGH, LED_BLUE, LOW);
	delay(1000);
	digitalWrite(LED_RED, LOW, LED_GREEN, LOW, LED_BLUE, HIGH);
	delay(1000);

	// original version of digitalWrite()
	digitalWriteDynamic(LED_BUILTIN, HIGH);
	delay(1000);
	digitalWriteDynamic(LED_BUILTIN, LOW);
	delay(1000);
}

Usage

Download Arduin-meta.hpp and

#include "Arduino-meta.hpp"

This file uses C++11 features so you must specify "-std=c++11" to compiler by "compiler.cpp.flags=...". See also:

• http://stackoverflow.com/questions/16224746/how-to-use-c11-to-program-the-arduino

digitalWrite / pinMode / digitalRead is replaced with static (template) version. You can use original version by digitalWriteDynamic / pinModeDynamic / digitalReadDynamic.

Background

Arduino's digitalWrite/pinMode/digitalRead always lookup tables in program memory to get a port register and a bit mask from a pin number. In most every case, thease functions arguments are static so looking up tables in runtime is needless.

This header file solve it at compile time with C++ templates.

Functions

digitalWrite(pin, value, ...)

Write multiple HIGH or LOW values to specified pins at once.

All pin must be reference to same port (eg. PORTB / PORTC / PORTD). If there are inconsistencies, it cause compile time error.

All arguments must be constant.

pinMode(pin, mode, ...)

Set multiple pin mode to INPUT, OUTPUT, or INPUT_PULLUP at once.

All pin must be reference to same port (eg. DDRB / DDRC / DDRD). If there are inconsistencies, it cause compile time error.

All arguments must be constant.

digitalRead(pin)

Read digital value HIGH or LOW from pin.

An argument must be constant.

digitalWriteDynamic(), pinModeDynamic(), digitalReadDynamic()

The original Arduino function which look up table at runtime.

Compile Time Error

If you specify invalid arguments to functions. This library report it as compile error. This is useful.

Test

make test

LISENCE

Same as Arduino (LGPL)