(Page 1 of 1 in this chapter)

Chapter 6

Line Interface Operations

: 6.1 Introduction
: 6.2 Identifying the Line Interface Type for a Timeslot
: 6.3 Setting Line Interface Gain
: 6.4 Retrieving Line Interface Gain

6.1 Introduction

This chapter documents operations specific to the AG Connect's line interfaces which you can perform in software. These operations include: Determining the type of line interface associated with a timeslot. Setting the input and output gain for a line interface, and determining the current gain setting.
These operations can be performed programmatically using CT Access Switching service function calls, or with swish utility commands. For more information, see the Switching Service Developer's Reference Manual.
Code samples in subsequent sections refer to the following macros: Macro Hex Value MVIP95_ANALOG_LINE_DEVICE 0x0002 MVIP95_CONFERENCE_DEVICE 0x0003 NMS_ANALOG_INTERFACE_TYPE 0x80000004 MVIP95_INPUT_GAIN 0x80000008 MVIP95_OUTPUT_GAIN 0x80000009 NMS_CONF_GET_SEAT_PARAMETER 0x80000010 NMS_CONF_SET_SEAT_PARAMETER 0x80000011 NMS_CONF_GET_CONF_DEFAULT 0x80000012 NMS_CONF_SET__CONF_DEFAULT 0x80000013 NMS_CONF_GET_SWITCH_DEFAULT 0x80000014 NMS_CONF_SET_SWITCH_DEFAULT 0x80000015 NMS_CONF_RELEASE_SEAT 0x80000016 NMS_CONF_RELEASE_CONF 0x80000017 NMS_CONF_GET_SWITCH_STATUS 0x80000018 NMS_CONF_GET_CONF_STATUS 0x80000019 Note: The macros shown above are defined in the mvip95.h and nmshw.h header files, and are subject to change.

Macro	Hex Value
`MVIP95_ANALOG_LINE_DEVICE`	`0x0002`
`MVIP95_CONFERENCE_DEVICE`	`0x0003`
`NMS_ANALOG_INTERFACE_TYPE`	`0x80000004`
`MVIP95_INPUT_GAIN`	`0x80000008`
`MVIP95_OUTPUT_GAIN`	`0x80000009`
`NMS_CONF_GET_SEAT_PARAMETER`	`0x80000010`
`NMS_CONF_SET_SEAT_PARAMETER`	`0x80000011`
`NMS_CONF_GET_CONF_DEFAULT`	`0x80000012`
`NMS_CONF_SET__CONF_DEFAULT`	`0x80000013`
`NMS_CONF_GET_SWITCH_DEFAULT`	`0x80000014`
`NMS_CONF_SET_SWITCH_DEFAULT`	`0x80000015`
`NMS_CONF_RELEASE_SEAT`	`0x80000016`
`NMS_CONF_RELEASE_CONF`	`0x80000017`
`NMS_CONF_GET_SWITCH_STATUS`	`0x80000018`
`NMS_CONF_GET_CONF_STATUS`	`0x80000019`

6.2 Identifying the Line Interface Type for a Timeslot

To determine the type of line interface associated with a specific timeslot, an application can call the CT Access Switching service function swiGetLocalTimeslotInfo. In the SWI_LOCALTIMESLOT_ARGS structure referenced in this call, the fields are set as follows:

Field

Setting to Get Line Interface Type

localstream

MVIP-95: 0
MVIP-90: 16

localtimeslot

A value corresponding to the timeslot to query (0 - 23).

deviceid

MVIP95_ANALOG_LINE_DEVICE

parameterid

NMS_ANALOG_INTERFACE_TYPE
The stream and timeslot specification method (MVIP-95 or MVIP-90) is determined when the AG Connect is opened as a switching device using swiOpenSwitch.
swiGetLocalTimeslotInfo also points to a buffer specific to the parameterid. When identifying the line interface type, this structure is defined as:

typedef struct { DWORD type ; } NMS_ANALOG_INTERFACE_TYPE_PARMS ;
The type component of the NMS_ANALOG_INTERFACE_TYPE_PARMS structure is formatted as shown in Figure 17: Figure 17. NMS_ANALOG_INTERFACE_TYPE_PARMS Type Component
The class is NMS_INTERFACE_AG_HYBRID, and the type is identified with one of the numbers defined in the table below: Value Line Interface Type 0x10 Operator Work Station 0x1F Operator Work Station with Ringing 0x78 Enhanced Loop Start (ELS) 0xFF No interface Note: Not all of the line interface types listed here are currently supported.
The following example code shows how to get the type of each line interface on a board:

/* * Identify the type of signaling module on a given terminus * --------------------------------------------------------- */ #include "ctadef.h" /* For CT Access */ #include "swidef.h" /* For CT Access Switching Service */ #include "mvip95.h" /* For MVIP95_ANALOG_LINE_DEVICE */ #include "nmshw.h" /* For NMS_LINE_INTERFACE_TYPE */ #include <stdlib.h> #include <stdio.h> DWORD myGetInterfaceType ( SWIHD swihd, /* From swiOpenSwitch() */ SWI_TERMINUS terminus, /* Target port */ DWORD *generation, /* Hardware generation */ DWORD *type /* Physical interface type */ ) { SWI_LOCALTIMESLOT_ARGS args; NMS_ANALOG_INTERFACE_TYPE_PARMS parms ; DWORD rc ; if ( terminus.bus != MVIP95_LOCAL_BUS ) return -1 ; /* Error - only applies to local bus */ args.localstream = terminus.stream ; args.localtimeslot = terminus.timeslot ; args.deviceid = MVIP95_ANALOG_LINE_DEVICE ; args.parameterid = NMS_ANALOG_INTERFACE_TYPE ; rc = swiGetLocalTimeslotInfo ( /* CT Access switch handle */ swihd, /* Target device and config item */ & args, /* Buffer (defined by parameterid) */ (void*) & parms, /* Buffer size in bytes */ sizeof(parms)); if ( rc == SUCCESS ) { *generation = GET_ANALOG_INTERFACE_CLASS(parms.type); *type = GET_ANALOG_INTERFACE_TYPE(parms.type); switch (*generation) { case NMS_INTERFACE_AG_HYBRID: printf("Class: NMS_INTERFACE_AG_HYBRID\n"); break; case NMS_INTERFACE_AG_SIGNALING_MODULE: printf("Class: NMS_INTERFACE_AG_SIGNALING_MODULE\n"); break; default: printf("Class: Unknown\n"); } printf ("Type : %02X\n", *type ) ; } else { printf ("swiGetLocalTimeslotInfo returns %d\n", rc ) ; } return rc ; }

Field	Setting to Get Line Interface Type
`localstream`	MVIP-95: `0` MVIP-90: `16`
`localtimeslot`	A value corresponding to the timeslot to query (`0` - `23`).
`deviceid`	`MVIP95_ANALOG_LINE_DEVICE`
`parameterid`	`NMS_ANALOG_INTERFACE_TYPE`

Value	Line Interface Type
`0x10`	Operator Work Station
`0x1F`	Operator Work Station with Ringing
`0x78`	Enhanced Loop Start (ELS)
`0xFF`	No interface

6.3 Setting Line Interface Gain

The input gain is the gain applied to the input from the network. You can set the input for individual line interfaces.
To set the line input gain for a line interface, call the CT Access Switching service function swiConfigLocalTimeslot. In the SWI_LOCALTIMESLOT_ARGS structure referenced in this call, set the fields as follows:

Field

Setting to Configure Gain

localstream

MVIP-95: 0
MVIP-90: 16

localtimeslot

The timeslot corresponding to the line interface (0 - 23).

deviceid

NMS_ANALOG_LINE_DEVICE

parameterid

For the input gain: MVIP95_INPUT_GAIN
The stream and timeslot specification method (MVIP-95 or MVIP-90) is determined when the AG Connect is opened as a switching device using swiOpenSwitch.
The buffer pointer set in swiConfigLocalTimeslot refers to a NMS_LINE_GAIN_PARMS structure that contains the gain value. Gain values are expressed in thousandths of a decibel. For example, 6dB is specified as 6000. Valid gain values are:

Device Type

Input Gain

Output Gain

Analog

· Enhanced Loop Start (ELS): 6000, 0, -3000, -6000,
-9000
· All others: 0, -3000, -6000, -9000

NA

Conference

0, -3000, -6000, -9000

0, -3000

Note: Applications using swiConfigLocalTimeslot and swiGetLocalTimeslotInfo must open the CT Access Switching Service. Refer to CT Access documentation for details.
Refer to the switch model in Chapter 5 to determine the local streams and timeslots on which line interface devices reside.
The following sample code shows how to configure gain applied to a signal received from the network:

#include "swidef.h" /* CT Access Switching Service */ #include "mvip95.h" /* MVIP-95 definitions */ #include "nmshw.h" /* NMS hardware-specific ddefinitions */ DWORD mySetReceiveGain ( SWIHD swihd, SWI_TERMINUS terminus, INT32 gain_dB ) { SWI_LOCALTIMESLOT_ARGS args; NMS_LINE_GAIN_PARMS device ; args.localstream = terminus.stream ; args.localtimeslot = terminus.timeslot ; args.deviceid = MVIP95_ANALOG_LINE_DEVICE ; args.parameterid = MVIP95_INPUT_GAIN ; device.gain = gain_dB * 1000 ; return swiConfigLocalTimeslot ( /* CT Access switch handle */ swihd, /* Target device and config item */ & args, /* Buffer (defined by parameterid) */ (void*) & device, /* Buffer size in bytes */ sizeof(device)); }
Gain can also be configured for conference seats. (See the Conferencing Developer's Reference Manual to learn how to do this.) When a line interface is connected to a conference, the actual gain value is the sum of the gain settings of the line interface and the conference seat.
If an attempt is made to connect a line interface to a conference seat, and the resulting gain value is too large, the connection is rejected and SWIERR_NO_PATH is returned.
If a connection already exists between a line interface and a conference seat, if an attempt is made to change either the interface or seat gain to a value which would make the sum of the values too large, the request is rejected and SWIERR_INVALID_PARAMETER is returned.

Field	Setting to Configure Gain
`localstream`	MVIP-95: `0` MVIP-90: `16`
`localtimeslot`	The timeslot corresponding to the line interface (`0` - `23`).
`deviceid`	`NMS_ANALOG_LINE_DEVICE`
`parameterid`	For the input gain: `MVIP95_INPUT_GAIN`

Device Type	Input Gain	Output Gain
Analog	· Enhanced Loop Start (ELS): `6000`, `0`, -`3000`, -`6000`, -`9000` · All others: `0`, -`3000`, -`6000`, -`9000`	`NA`
Conference	`0`, -`3000`, -`6000`, -`9000`	`0`, `-3000`

6.4 Retrieving Line Interface Gain

You can query for the current the input gain setting of an individual line interface.
To determine the input gain for a line interface, call the CT Access Switching service function swiGetLocalTimeslotInfo. In the SWI_LOCALTIMESLOT_ ARGS structure referenced in this call, set the fields as follows:

Field

Setting to Determine Gain

localstream

MVIP-95: 0
MVIP-90: 16

localtimeslot

The timeslot corresponding to the line interface (0 - 23).
Note: These must be line interface stream:timeslots.
deviceid

MVIP95_ANALOG_LINE_DEVICE

parameterid

For the input gain: MVIP95_INPUT_GAIN
The stream and timeslot specification method (MVIP-95 or MVIP-90) is determined when the AG Connect is opened as a switching device using swiOpenSwitch.
The buffer pointer set in swiConfigLocalTimeslot refers to a NMS_LINE_GAIN_PARMS structure that contains the gain value. Gain values are expressed in thousandths of a decibel. For example, 6dB is specified as 6000.
Possible gain values are: Device Type Input Gain Output Gain Analog · Enhanced Loop Start (ELS): 6000, 0, -3000, -6000, -9000 · All others: 0, -3000, -6000, -9000 NA Conference 0, -3000, -6000, -9000 0, -3000
The following sample code shows how to retrieve line gain applied to signal received from network:

#include "swidef.h" /* CT Access Switching Service */ #include "mvip95.h" /* MVIP-95 definitions */ #include "nmshw.h" /* NMS hardware-specific definitions */ DWORD myGetReceiveGain ( SWIHD swihd, SWI_TERMINUS terminus, INT32* gain_dB ) { SWI_LOCALTIMESLOT_ARGS args; NMS_LINE_GAIN_PARMS device ; DWORD rc ; args.localstream = terminus.stream ; args.localtimeslot = terminus.timeslot ; args.deviceid = MVIP95_ANALOG_LINE_DEVICE ; args.parameterid = MVIP95_INPUT_GAIN ; rc = swiGetLocalTimeslotInfo ( /* CT Access switch handle */ swihd, /* Target device and config item */ & args, /* Buffer (defined by parameterid) */ (void*) & device, /* Buffer size in bytes */ sizeof(device)); *gain_dB = device.gain / 1000 ; return rc ; }
Gain can also be configured for conference seats. When a line interface is connected to a conference, the actual gain value is the sum of the gain settings of the line interface and the conference seat. The following code sample shows how to calculate this value:

void myGetGain(SWIHD agcxhd, DWORD *gain)
{
SWI_LOCALTIMESLOT_ARGS args;
DWORD tmp;

/*
** Assume that there exists a connection between
** 16:6 and 20:6
*/

/* First, get line interface gain */
args.localstream = 0;
args.deviceid = MVIP95_ANALOG_LINE_DEVICE;
args.parameterid = MVIP95_INPUT_GAIN;
args.localtimeslot = 6;
swiGetLocalTimeslotInfo(agcxhd, &args, gain, sizeof(*gain));

/* Now get conference chip gain */
args.localstream = 20;
args.deviceid = MVIP95_CONFERENCE_DEVICE;
args.parameterid = MVIP95_INPUT_GAIN;
args.localtimeslot = 6;
swiGetLocalTimeslotInfo(agcxhd, &args, &tmp, sizeof(tmp));

/* Now add the two together, and return value */
*gain += tmp;
}
For more information about determining the gain of a conference seat, see the Conferencing Developer's Reference Manual.

Field	Setting to Determine Gain
`localstream`	MVIP-95: `0` MVIP-90: `16`
`localtimeslot`	The timeslot corresponding to the line interface (0 - 23). Note: These must be line interface stream:timeslots.
`deviceid`	`MVIP95_ANALOG_LINE_DEVICE`
`parameterid`	For the input gain: `MVIP95_INPUT_GAIN`

Device Type	Input Gain	Output Gain
Analog	· Enhanced Loop Start (ELS): `6000`, `0`, -`3000`, -`6000`, -`9000` · All others: `0`, -`3000`, -`6000`, -`9000`	`NA`
Conference	`0`, -`3000`, -`6000`, -`9000`	`0`, `-3000`

(Page 1 of 1 in this chapter)

tech_support@nmss.com