Windows regards most sound cards as stereo devices. In other words, each sound card should have two channels, with left being the first and right being the second. A channel is an independent audio input or output of an audio device. Within V+, VComm looks at this in a slightly different way. It enumerates channels starting with the first device on through the list of devices as specified by the Audio Device Order within V+.
The table below presents an example of a system configured with a USB PTT Headset Adapter, an onboard Sigma Tel Audio device, and an 8 channel SMx system. In the left-most column we see the device numbering as regarded by Windows. In the right-most column we see how VComm numbers these channels. All SMx channels can be used by VComm due to the nature of SMx – that of dealing with audio on a single channel basis. Note that SMx must still adhere to the Windows convention of devices in order to work with the DirectSound API, but internally it does not deal with audio in a stereo device manner.
When a V+ object has a static data element named Device, it expects the number provided to adhere to the Windows device numbering scheme. When an object has a Channel static data element, it expects it to follow the numbering scheme in the third column of the table below.
|
Windows Device Number |
Device Name |
V+/SMx/VComm Channel Number | |
|
1 |
Left |
PTT Headset Adapter |
1 |
|
Right |
2 | ||
|
2 |
Left |
Sigma Tel Audio |
3 |
|
Right |
4 | ||
|
3 |
Left |
SMx 01/02 |
5 |
|
Right |
6 | ||
|
4 |
Left |
SMx 03/04 |
7 |
|
Right |
8 | ||
|
5 |
Left |
SMx 05/06 |
9 |
|
Right |
10 | ||
|
6 |
Left |
SMx 07/08 |
11 |
|
Right |
12 | ||