Module_SoundDMA

Module: SoundDMA

Status summary

Component	Section	32-bit	64-bit	Claimant	Source	Repo summary
SoundDMA	ROM modules					not built in repo, not tested in repo

Development status

Completeness

Functionality	Commands	SWIs	Services	Uses Services	TOTAL
0.00%	0.00%	0.00%	0.00%	0.00%	0.00%

Summary

SoundDMA is the Level 0 hardware sound-output driver. It owns and refills the double-buffered sound DMA stream across the supported VIDC/MEMC/IOMD variants (including the VIDC1 A5000 path and VIDC20/IOMD or MEMC configurations). It accepts the legacy 8-bit mu-law multi-channel stream from SoundChannels, then—when configured for 16-bit output—converts it to signed 16-bit stereo, optionally lets an installed linear mixer overwrite or mix the buffer, and performs mono/oversampling processing. At each DMA buffer interrupt it invokes the registered Level 2 SoundScheduler before the Level 1 fill routine. This is the hardware-facing root of the traditional three-level RISC OS sound system.

Relationships

Discovered features

• Has nvram state
• Has services
• Has services fast
• Has swis
• Is hardware specific
• Uses console output
• Uses dynamic area
• Uses messagetrans

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Provides

Functionality

In 32bit	In 64 bit	Interface
🔲	🔲	Hardware driver
🔲	🔲	Issues service on start and shutdown
🔲	🔲	Provides/calls Log handler
🔲	🔲	Provides/calls Linear handler
🔲	🔲	Provides/calls scheduler
🔲	🔲	Enumerates provided sample rates
🔲	🔲	Allows selection of sample rates
🔲	🔲	Can disable sound
🔲	🔲	Can route to speaker or jack

Commands

In 32bit	In 64 bit	Interface
🔲	🔲	*Audio
🔲	🔲	*Configure SoundSystem
🔲	🔲	*SoundGain
🔲	🔲	*Speaker
🔲	🔲	*Stereo

SWIs

In 32bit	In 64 bit	Interface
🔲	🔲	Sound_Configure (&40140)
🔲	🔲	Sound_Enable (&40141)
🔲	🔲	Sound_Stereo (&40142)
🔲	🔲	Sound_Speaker (&40143)
🔲	🔲	Sound_Mode (&40144)
🔲	🔲	Sound_LinearHandler (&40145)
🔲	🔲	Sound_SampleRate (&40146)

Services

In 32bit	In 64 bit	Interface
🔲	🔲	Service_Portable
🔲	🔲	Service_Reset

Vectors

None

Events

None

UpCalls

None

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Issues calls to

Services

In 32bit	In 64 bit	Interface
🔲	🔲	Service_Sound

Vectors

None

Events

None

UpCalls

None

Modules

• MessageTrans
• Portable
• Sound