Adding Speakerphone Support
Speakerphone capabilities can be supported by using the following INF file entries: SpeakerPhoneSpecs, SpeakerPhoneEnable, SpeakerPhoneDisable, SpeakerPhoneMute, SpeakerPhoneUnMute and SpeakerPhoneSetVolumeGain. For example, here are the six INF file entries from SmpVoice.inf.
HKR,, SpeakerPhoneSpecs, 1, 00,00,00,00, 0f,00,00,00, 03,00,00,00, 00,00,00,00
HKR, SpeakerPhoneEnable, 1,, "at#vls=5<cr>"
HKR, SpeakerPhoneDisable, 1,, "at#vls=0<cr>"
HKR, SpeakerPhoneMute, 1,, "at#spk=0,,,<cr>"
HKR, SpeakerPhoneUnMute, 1,, "at#spk=1,,,<cr>"
HKR, SpeakerPhoneSetVolumeGain,1,, "at#spk=,<Vol>,<Gain><cr>"
The four values in the SpeakerPhoneSpecs entry define the minimum and maximum speakerphone volumes, as well as the minimum and maximum gain. The SpeakerPhoneSpecs entry must be included even if all four values are zero. Use ProCalc to create the SpeakerPhoneSpecs entry, as described in Creating Voice Modem INF File Entries with ProCalc.
The SpeakerPhoneSetVolumeGain entry values are used to scale the speakerphone volume and gain when TAPI passes Unimodem a speaker volume setting. Scaling is based on the values assigned in the SpeakerPhoneSpecs entry. For more information about speakerphone volume and gain scaling, see Modem INF File Entries.
Set the following INF file entries to command strings that Unimodem can send to the voice modem to accomplish the indicated functions: SpeakerPhoneEnable, SpeakerPhoneDisable, SpeakerPhoneMute, and SpeakerPhoneUnMute.
Volume and gain must both be set for modems with volume control. If there is no gain control, use AT volume control commands that approximate gain control.