h6. [[SoundDMA]] h6(. » [[SoundDMA SWI Calls|SWI Calls]] h6((. » [[Sound_Mode]] h6(((. » Sound_Mode 0 h2. Sound_Mode 0 h5. (SWI &40144) |_<^{width:4em}. Entry | | |<^. R0 |<^. 0 (reason code) | |_<^{width:4em}. Exit | | |/2<^. R0 |<^. 0 -> only 8 bit sound is available | |<^. 1 -> 16 bit sound available (plus emulated 8 bit sound) | |/8<^. R1 |<^. 0 if 16 bit sound unavailable. Otherwise: | |<^. Bits 0-3: Sound output format and clock control status: | |<^. 1 -> 16-bit linear output, 44k1, 22k05, 11k025 and selected original rates | |<^. 2 -> 16-bit linear output, internal clock, selected original rates only | |<^. 3 -> 16-bit linear output, external master clock source, custom rates only | |<^. Bit 4: Oversampling mode (1 = enabled) | |<^. Bit 5: Mono conversion status (1 = enabled) | |<^. Bits 6-31: Reserved for future expansion (0 returned) | h4. Use This SWI is used to detect the presence of the 16 bit sound system and to read its status and features. h4. Notes If R0 is 1 on exit, it indicates that the following features are available: * [[Sound_Mode]] with non-zero reason codes * [[Sound_LinearHandler]] * [[Sound_SampleRate]] If R0 is 0 then the above features are unavailable and no attempt should be made to use them. Use of bits 0-3 of R1 to determine the support sample rates is deprecated. [[Sound_SampleRate]] should be used instead. Bit 4 of R1 reflects the desired oversampling state, as set by [[Sound_Mode 1]]. Note that even if bit 4 is set, it does not guarantee that oversampling is currently in use - for certain sound system configurations, hardware or software limits may prevent it from being used. h4. See also * [[Sound_SampleRate]] * [[Sound_Mode 1]] * [[Sound_Mode 3]]