psg.h File Reference

PSG support. More...

Go to the source code of this file.

Defines
#define	PSG_PORT   0xC00011
#define	PSG_ENVELOPE_MIN   15
#define	PSG_ENVELOPE_MAX   0
#define	PSG_NOISE_TYPE_PERIODIC   0
#define	PSG_NOISE_TYPE_WHITE   1
#define	PSG_NOISE_FREQ_CLOCK2   0
#define	PSG_NOISE_FREQ_CLOCK4   1
#define	PSG_NOISE_FREQ_CLOCK8   2
#define	PSG_NOISE_FREQ_TONE3   3
Functions
void	PSG_init ()
	Initialize PSG chip.
void	PSG_write (u8 data)
	Write to PSG port.
void	PSG_setEnvelope (u8 channel, u8 value)
	Set envelope level.
void	PSG_setTone (u8 channel, u16 value)
	Set tone.
void	PSG_setFrequency (u8 channel, u16 value)
	Set frequency.
void	PSG_setNoise (u8 type, u8 frequency)
	Set noise type and frequency.

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Detailed Description

PSG support.

Author:

Stephane Dallongeville

Date:

08/2011

This unit provides access to the PSG through the 68000 CPU

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Define Documentation

#define PSG_ENVELOPE_MAX   0

Maximum PSG envelope value.

#define PSG_ENVELOPE_MIN   15

Minimum PSG envelope value.

#define PSG_NOISE_FREQ_CLOCK2   0

Noise frequency = PSG clock / 2 (less coarse).

#define PSG_NOISE_FREQ_CLOCK4   1

Noise frequency = PSG clock / 4.

#define PSG_NOISE_FREQ_CLOCK8   2

Noise frequency = PSG clock / 8 (more coarse).

#define PSG_NOISE_FREQ_TONE3   3

Noise frequency = Tone generator #3.

#define PSG_NOISE_TYPE_PERIODIC   0

Periodic noise type (like low-frequency tone).

#define PSG_NOISE_TYPE_WHITE   1

White noise type (hiss).

#define PSG_PORT   0xC00011

PSG port address.

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Function Documentation

void PSG_setEnvelope	(	u8	channel,
		u8	value
	)

Set envelope level.

Parameters:

channel	Channel we want to set envelope (0-3).
value	Envelope level to set (PSG_ENVELOPE_MIN - PSG_ENVELOPE_MAX).

Set envelope level for the specified PSG channel.

void PSG_setFrequency	(	u8	channel,
		u16	value
	)

Set frequency.

Parameters:

channel	Channel we want to set frequency (0-3).
value	Frequency value to set in Hz (0-4095).

Set frequency for the specified PSG channel.
This method actually converts the specified frequency value in PSG tone value.

void PSG_setNoise	(	u8	type,
		u8	frequency
	)

Set noise type and frequency.

Parameters:

type	Noise type, accepted values are: PSG_NOISE_TYPE_PERIODIC PSG_NOISE_TYPE_WHITE
frequency	Noise frequency, accepted values are: PSG_NOISE_FREQ_CLOCK2 PSG_NOISE_FREQ_CLOCK4 PSG_NOISE_FREQ_CLOCK8 PSG_NOISE_FREQ_TONE3

void PSG_setTone	(	u8	channel,
		u16	value
	)

Set tone.

Parameters:

channel	Channel we want to set tone (0-3).
value	Tone value to set (0-1023).

Set direct tone value for the specified PSG channel.

void PSG_write

(

u8

data

)

Write to PSG port.

Parameters:

data	value to write to the port.

Write the specified value to PSG data port.