Game Development with Arduino - Arduino - page 217

sprite2x2(sprite #, position x, position y, image #, palette, rotation,
collision) : Sets a 2×2 sprite to be drawn at the center four corners; uses same parameters
as sprite() .

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ascii() : Loads Gameduino's standard font.

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putstr(position x, position y, string) : Prints a string encapsulated in quotes at the
position (x, y). Needs ascii() to be run first to load the default font.

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voice(voice #, wave type, frequency, left volume, right volume) : Sets a tone to be
played out of the Gameduino's audio port. Table 11-2 describes the voice() parameters.

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Table 11-2. Arguments for the voice() Function

Parameter Description

voice # Individual hardware voice number used to output

sound; takes a value between 0 and 63

wave type Waveform (0 is sine wave, 1 is noise)

frequency Frequency in quarter-Hertz (e.g., 100 Hz is 400)

left volume , right volume Amplitude of the wave output per channel; takes a value

between 0 and 255; total volume for all voices should be
less than or equal to 255

Some of the functions require a memory address to be able to read or place data into the Gameduino. The library
also defines some keywords that are helpful when calling functions that deal with memory addresses. Table 11-3
provides the name, address, and descriptor; the keywords referenced are the common memory locations for
developing games.

Table 11-3. Useful Keywords Specific to the Gameduino's memory sructure and begging adresse locations.
memory addresses * Byte length = total bytes in memory

Keyword Address Description

RAM_CHR 0x1000

Screen characters (256 ×16 = 4096 bytes)

RAM_PAL 0x2000

Screen character palette (256×8 = 2048 bytes)

RAM_SPR 0x3000

Sprite control (512×4 = 2048 bytes)

RAM_SPRPAL 0x3800

Sprite palettes (4×256 = 2048 bytes)

RAM_SPRIMG 0x4000

Sprite image (64×256 = 16384 bytes)

PALETTE16A 0x2840

16-color palette RAM A (32 bytes)

PALETTE16B 0x2860

16-color palette RAM B (32 bytes)

PALETTE4A 0x2880

4-color palette RAM A (8 bytes)

PALETTE4B 0x2888

4-color palette RAM A (8 bytes)

VOICES 0x2a00

Voice controls