Creates an MSPP media channel.

DWORD mspCreateChannel (CTAHD ctahd,
MSP_CHANNEL_ADDR* addr,
MSP_CHANNEL_PARMS* parm,
MSPHD* chnhd)

ctahd CT Access handle used to open the MSPP service.

addr Pointer to the MSP_CHANNEL_ADDR structure, as shown:

typedef struct_tag_MSP_CHANNEL_ADDR
{
  DWORD            nBoard;   /* Channel location (board number)*/
  MSP_TYPE_CHANNEL pChanType; /* Type of channel to create     */
} MSP_CHANNEL_ADDR;

parm Reserved for future use. Until the MSP_CHANNEL_PARMS structure is defined, NULL is passed.

chnhd Pointer to an MSPP return channel handle.

• SUCCESS
• CTAERR_BAD_ARGUMENT
  The function argument had an invalid value or a required pointer argument was NULL.
• CTAERR_INVALID_CTAHD
  The CTA context handle is invalid.
• CTAERR_INVALID_HANDLE
  An invalid handle was passed as an argument to this function.
• MSPERR_CHANNEL_NOT_DEFINED
  The MSPP channel name specified is not defined.

• MSPEVN_CREATE_CHANNEL_DONE
  Generated when an MSPP channel is created in response to a mspCreateChannel function call. The event.value field can contain the following:
• SUCCESS
• MSPRSN_FAILED_TO_ALLOCATE
  The MSPP service is unable to allocate on-board resources.

When invoking mspCreateChannel, provide a CT Access context handle (ctahd), and specify the channel type and the board number where the channel will be created. When it creates the MSPP channel, the MSPP service returns a unique channel object handle (chnhd) that the application can use to configure and control the channel. Once you have created an MSPP channel and enabled it, you can use it to connect MSPP endpoints to create a media path for voice or fax data.

Supported MSPP channels include:

Channel ID	Description
FaxRelayFullDuplex	Processes a full duplex data stream by encoding, decoding, modulating, and demodulating T.38 fax data.
FaxRelayStandby	Waits in "standby" mode (still disabled) until it detects a T.38 packet. Then it returns a MSPEVN_T38PACKET_DETECT event to the application. When enabled, transfers and processes T.38 fax data.
G711DecodeSimplex	Processes a simplex data stream by decoding voice data according to the G.711 algorithm.
G711EncodeSimplex	Processes a simplex data stream by encoding voice data according to the G.711 algorithm.
G711FullDuplex	Processes a full duplex data stream by encoding and decoding voice data according to the G.711 algorithm.
G723DecodeSimplex	Processes a simplex data stream by decoding voice data according to the G.723.1/A algorithm.
G723EncodeSimplex	Processes a simplex data stream by encoding voice data according to the G.723.1/A algorithm.
G723FullDuplex	Processes a full duplex data stream by encoding and decoding voice data according to the G.723.1/A algorithm.
G726DecodeSimplex	Processes a simplex data stream by decoding voice data according to the G.726 algorithm.
G726EncodeSimplex	Processes a simplex data stream by encoding voice data according to the G.726 algorithm.
G726FullDuplex	Processes a full duplex data stream by encoding and decoding voice data according to the G.726 algorithm.
G729DecodeSimplex	Processes a simplex data stream by decoding voice data according to the G.729A/B algorithm.
G729EncodeSimplex	Processes a simplex data stream by encoding voice data according to the G.729A/B algorithm.
G729FullDuplex	Processes a full duplex data stream by encoding and decoding voice data according to the G.729A/B algorithm.

mspDestroyChannel, mspDisableChannel, mspEnableChannel, mspSendCommand

mspChanAddr.nBoard = DEFAULT_BOARDID;
mspChanAddr.channelType = G711FullDuplex;
ret = mspCreateChannel( hCta, &mspChanAddr, NULL, &hChan );
if (ret != SUCCESS)
    return FAILURE;
ctaWaitEvent( hCta, &Event, CTA_WAIT_FOREVER );
// Check the reason code
if ( Event.id    != MSPEVN_CREATE_CHANNEL_DONE ||
     Event.value != CTA_REASON_FINISHED )
    return FAILURE;