kaspi314/nibblearray

Arduino library for a compact array of nibbles (4 bit units)

nibbleArray

Arduino library for a compact array of nibbles (4 bit units)

Description

A nibble is a 4 bit element, which can hold a value 0..15 (0..F in HEX). It can be seen as an uint4_t type.

The nibbleArray is an array that stores 2 nibbles in a byte therefor it is twice as small as a normal array.

The current implementation can hold 510 elements. This is due a limitation of the UNO which can alloc max 255 bytes in one malloc() call.

This NIBBLEARRAY_MAXSIZE can be defined compiletime "-D NIBBLEARRAY_MAXSIZE" or one can adjust it in the library if other platforms can allocate more memory.

Interface

The interface of the nibbleArray is straightforward:

• nibbleArray(uint16_t size) constructor
• set(index, value) set a value in the nibbleArray, index must be in range otherwise 0xFF will be returned.
• get(index) get value from index, index must be in range otherwise 0xFF will be returned
• size() returns the size of the array.
• clear() set all elements to 0;
• SetAll(value) set all elements to value (0..15)

Operation

See examples

Todo

• todo's to issues
• implement NIBBLEARRAY_ERROR_VALUE for set and setAll ??
• allow larger allocations for non AVR, how?
• setAll( f() ) - fill the array by calling a function n times?
• align interface with boolArray and bitArray.