h6. [[ScreenModes]] h6(. » [[ScreenModes SWI Calls|SWI Calls]] h6((. » [[ScreenModes_ReadInfo]] h6(((. » ScreenModes_ReadInfo 2 h2. ScreenModes_ReadInfo 2 h5. (SWI &487C0) |_<^{width:4em}. Entry | | |<^. R0 |<^. 2 | |_<^{width:4em}. Exit | | |<^. R0 |<^. Speaker mask | |<^. R1 |<^. Validity mask | |\2<^. All other registers preserved| h4. Use This call provides a means for software to determine which speakers may be available on a given display. Normally this information is determined by reading the displays EDID. Because the speaker mask is an optional part of the EDID, two values are returned: the speaker mask as reported from the monitor (in R0), and a validity mask (in R1) which indicates which bits of R0 have been specified. The following table can be used as a guide to determine whether a given speaker is available or not: |_<^. Speaker mask bit value |_<^. Validity mask bit value |_<^. Interpretation | |<^. 0 |<^. 0 | Monitor did not provide information - speaker may or may not be present | |<^. 0 |<^. 1 | Speaker is not present | |<^. 1 |<^. 0 | Reserved | |<^. 1 |<^. 1 | Speaker is present | h4. Notes Bit allocation in the two words follows the same scheme as the CEA 861 speaker allocation data block: |_<^{width:4em}. Bit |_<^. Interpretation | |<^. 0 |<^. Front Left & Front Right | |<^. 1 |<^. LFE | |<^. 2 |<^. Front Center | |<^. 3 |<^. Rear Left & Rear Right | |<^. 4 |<^. Rear Center | |<^. 5 |<^. Front Left Center & Front Right Center | |<^. 6 |<^. Rear Left Center & Rear Right Center | |<^. 7+ |<^. Reserved | h4. See Also * [[ScreenModes_EnumerateAudioFormats]]