Global Call ISDN Technology User's Guide: 5.13. DCHAN

5.13. DCHAN_CFG

When using DM3 boards, the DCHAN_CFG data structure is not supported.

When using Springware boards, the DCHAN_CFG data structure contains D-channel configuration block information. The D-channel configuration block sets the configuration of the Digital Subscriber Loop (DSL) for BRI applications.

The structure is defined as follows:
typedef struct {
   byte           layer2_access;          /* Layer 2 or full stack */
   byte           switch_type;            /* Layer 3 switch type */
   byte           switch_side;            /* Network or User side */
   byte           number_of_endpoints;    /* # of logical data links */
   byte           feature_controlA;       /* Firmware feature mask A */
   byte           feature_controlB;       /* Firmware feature mask B */
   byte           rfu_1;                  /* Reserved for future use */
   byte           rfu_2;                  /* Reserved for future use */
   struct { 
      byte        tei_assignment;         /* Auto assignment or Fixed TEI terminal */
      byte        fixed_tei_value;        /* TEI value if Fixed TEI terminal */
      union {
         struct {
            byte  auto_init_flag;         /* Auto initializing term or not */
            byte  SPID[MAX_SPID_SIZE];    /* SPID for terminal, NULL
                                             terminated string. */
            byte  rfu_1;
            byte  rfu_2;
         } no_am; /* North America */
    } protocol_specific;
   } user;
  #define RFU_COUNT 8 /* # of reserve for future use bytes */
   byte rfu[RFU_COUNT]; 
   union {
      struct {
         long     T302;
         long     T303;
         long     T304;
         long     T305;
         long     T306;
         long     T308;
         long     T309;
         long     T310;
         long     T312;
         long     T322;
      } nt;
      struct {
         long     T303;
         long     T304;
         long     T305;
         long     T308;
         long     T310;
         long     T312;
         long     T313;
         long     T318;
         long     T319;
      } te;
   } tmr;
} DCHAN_CFG, *DCHAN_CFG_PTR; 
The possible values for the DCHAN_CFG structure are listed below. All components of the DCHAN_CFG structure that pertain to your configuration must be set. There are no default values.

Note: The T3xx values for defining the Layer 3 timer can be used for BRI/2, BRI/SC and PRI protocols. All of the other values in the structure are applicable only to BRI/SC.
Table 54. DCHAN_CFG Field Descriptions and Values

Type

Description

Values

layer2_access Boolean value used to configure the DSL for direct layer 2 access or for full stack access.
#define LAYER_2_ONLY 0
#define FULL_ISDN_STACK 1
Where:

LAYER_2_ONLY = ISDN access at layer 2 (If LAYER_2_ONLY is selected, no other parameters are required)·
FULL_ISDN_STACK = ISDN access at L3 call control

switch_type Basic rate protocol (switch type) for DSL. Multiple run-time selectable switch types are available.
typedef enum {
ISDN_INVALID_SWITCH=0x80,
ISDN_BRI_5ESS, ISDN_BRI_DMS100,
ISDN_BRI_NTT, ISDN_BRI_NET3,
ISDN_BRI_NI1, ISDN_BRI_NI2 }
IsdnSwitchType;
Where:

ISDN_BRI_5ESS = ATT 5ESS BRI
ISDN_BRI_DMS100 = Northern Telecom DMS100 BRI
ISDN_BRI_NTT = Japanese INS-Net 64 BRI
ISDN_BRI_NET3 = EuroISDN BRI
ISDN_BRI_NI1 = National ISDN 1
ISDN_BRI_NI2 = National ISDN 2

switch_side Boolean value defining whether the DSL should be configured as the Network side (NT) or the User side (TE).
#define USER_SIDE 0
#define NETWORK_SIDE 1
Where:

USER_SIDE = User side of ISDN protocol
NETWORK_SIDE = Network side of ISDN protocol

number_of_ endpoints Number of logical data links to be supported. 1 to MAX_DLINK, where MAX_DLINK is currently set to 8. This field only has significance when configuring the DSL as the NETWORK side.

feature_controlA Firmware feature control field A. This is a bit mask field for setting features in the firmware. The following defines are used to configure the firmware features. The lowest two bits provide a combination of four possible settings for the TONE feature.
#define NO_PCM_TONE
0x00#define ULAW_PCM_TONE
0x01#define ALAW_PCM_TONE
0x02#define DEFAULT_PCM_TONE
0x03#define
SENDING_COMPLETE_ATTACH
0x04#define USER_PERST_L2_ACT
0x08#define
HOST_CONTROLLED_RELEASE 0x10
Where:

NO_PCM_TONE = Disable firmware from providing tones and set default encoding according to switch type
ULAW_PCM_TONE = Provide tones and use ULAW encoding for B channel tones
ALAW_PCM_TONE = Provide tones and use ALAW encoding for B channel tones
DEFAULT_PCM_TONE = Provide tones and use default encoding for B channel tones according to the switch type setting
SENDING_COMPLETE_ATTACH = Add Sending Complete IE to SETUP message
USER_PERST_L2_ACT = Persistent L2 activation on User side
HOST_CONTROLLED_RELEASE = Delay RELEASE reply until host issues gc_ReleaseCall( )

feature_controlB Firmware feature control field. This is a bit mask field for setting features in the firmware. Currently not used.

rfu_1 & rfu_2 Reserved for future use. Currently not used.

tei_assignment Applies to User Side only. It specifies if the terminal has a fixed TEI or an auto-assigning TEI. If it is fixed, then "fixed_tei_value" must be specified (see below).
#define AUTO_TEI_TERMINAL 0
#define FIXED_TEI_TERMINAL 1
Where:

AUTO_TEI_TERMINAL = auto TEI assigning Term
FIXED_TEI_TERMINAL = Fixed TEI assigning Term

fixed_tei_value Defines the TEI to be used for a fixed TEI assigning terminal. 0 to 63 (Required when tei_assignment = FIXED_TEI_TERMINAL)

auto_init_flag Boolean value defining whether or not the terminal is an auto initializing terminal. This field applies only when configuring the DSL as the User side and only to North American protocols.
#define AUTO_INIT_TERMINAL 0
#define NON_INIT_TERMINAL 1
Where:

AUTO_INIT_TERMINAL = auto initializing terminal
NON_INIT_TERMINAL = non-auto initializing term

SPID Defines the assigned Service Provider Identifier (SPID) value for terminal initialization. It is only applicable to User side US switches. When you set the SPID, it is assigned to both bearer channels associated with the D channel. ASCII digit string limited to the digits 0-9 and limited in length to MAX_SPID_SIZE Where: MAX_SPID_SIZE = (20+1) (Required when auto_init_flag = AUTO_INIT_TERMINAL. Most North American switches require a SPID.)

no_am.rfu_1 & rfu_2 Reserved for future use. Currently not used.

rfu[RFU_COUNT] Array of fields reserved for future use. Specified values are in 10 millisecond increments. For example, a specified value of 100 is equivalent to 1 second. Possible values are:

0 = Default value for switch·
1 = Default value for switch·
0 < n < 1 = Timer value in tens of milliseconds
Note: Incorrect or unreasonable timer settings will result in undesirable effects to calls as well as the call control stack. Before you override the default values, you need to understand the timer meanings and their interdependencies.

T3xx (T302, T303, T304, T305, T306, T308, T309, T310, T312, T313, T318, T319, T322) Defines the Layer 3 timer values. See Q.931 specification and corresponding switch specifications for exact definitions and default values for these timers. Not all timers are applicable to all of the switches.

**Table 54. DCHAN_CFG Field Descriptions and Values**
Type	Description	Values
layer2_access	Boolean value used to configure the DSL for direct layer 2 access or for full stack access.	#define LAYER_2_ONLY 0 #define FULL_ISDN_STACK 1 Where: LAYER_2_ONLY = ISDN access at layer 2 (If LAYER_2_ONLY is selected, no other parameters are required)· FULL_ISDN_STACK = ISDN access at L3 call control
switch_type	Basic rate protocol (switch type) for DSL. Multiple run-time selectable switch types are available.	typedef enum { ISDN_INVALID_SWITCH=0x80, ISDN_BRI_5ESS, ISDN_BRI_DMS100, ISDN_BRI_NTT, ISDN_BRI_NET3, ISDN_BRI_NI1, ISDN_BRI_NI2 } IsdnSwitchType; Where: ISDN_BRI_5ESS = ATT 5ESS BRI ISDN_BRI_DMS100 = Northern Telecom DMS100 BRI ISDN_BRI_NTT = Japanese INS-Net 64 BRI ISDN_BRI_NET3 = EuroISDN BRI ISDN_BRI_NI1 = National ISDN 1 ISDN_BRI_NI2 = National ISDN 2
switch_side	Boolean value defining whether the DSL should be configured as the Network side (NT) or the User side (TE).	#define USER_SIDE 0 #define NETWORK_SIDE 1 Where: USER_SIDE = User side of ISDN protocol NETWORK_SIDE = Network side of ISDN protocol
number_of_ endpoints	Number of logical data links to be supported.	1 to MAX_DLINK, where MAX_DLINK is currently set to 8. This field only has significance when configuring the DSL as the NETWORK side.
feature_controlA	Firmware feature control field A. This is a bit mask field for setting features in the firmware.	The following defines are used to configure the firmware features. The lowest two bits provide a combination of four possible settings for the TONE feature. #define NO_PCM_TONE 0x00#define ULAW_PCM_TONE 0x01#define ALAW_PCM_TONE 0x02#define DEFAULT_PCM_TONE 0x03#define SENDING_COMPLETE_ATTACH 0x04#define USER_PERST_L2_ACT 0x08#define HOST_CONTROLLED_RELEASE 0x10 Where: NO_PCM_TONE = Disable firmware from providing tones and set default encoding according to switch type ULAW_PCM_TONE = Provide tones and use ULAW encoding for B channel tones ALAW_PCM_TONE = Provide tones and use ALAW encoding for B channel tones DEFAULT_PCM_TONE = Provide tones and use default encoding for B channel tones according to the switch type setting SENDING_COMPLETE_ATTACH = Add Sending Complete IE to SETUP message USER_PERST_L2_ACT = Persistent L2 activation on User side HOST_CONTROLLED_RELEASE = Delay RELEASE reply until host issues gc_ReleaseCall( )
feature_controlB	Firmware feature control field. This is a bit mask field for setting features in the firmware.	Currently not used.
rfu_1 & rfu_2	Reserved for future use.	Currently not used.
tei_assignment	Applies to User Side only. It specifies if the terminal has a fixed TEI or an auto-assigning TEI. If it is fixed, then "fixed_tei_value" must be specified (see below).	#define AUTO_TEI_TERMINAL 0 #define FIXED_TEI_TERMINAL 1 Where: AUTO_TEI_TERMINAL = auto TEI assigning Term FIXED_TEI_TERMINAL = Fixed TEI assigning Term
fixed_tei_value	Defines the TEI to be used for a fixed TEI assigning terminal.	0 to 63 (Required when tei_assignment = FIXED_TEI_TERMINAL)
auto_init_flag	Boolean value defining whether or not the terminal is an auto initializing terminal. This field applies only when configuring the DSL as the User side and only to North American protocols.	#define AUTO_INIT_TERMINAL 0 #define NON_INIT_TERMINAL 1 Where: AUTO_INIT_TERMINAL = auto initializing terminal NON_INIT_TERMINAL = non-auto initializing term
SPID	Defines the assigned Service Provider Identifier (SPID) value for terminal initialization. It is only applicable to User side US switches. When you set the SPID, it is assigned to both bearer channels associated with the D channel.	ASCII digit string limited to the digits 0-9 and limited in length to MAX_SPID_SIZE Where: MAX_SPID_SIZE = (20+1) (Required when auto_init_flag = AUTO_INIT_TERMINAL. Most North American switches require a SPID.)
no_am.rfu_1 & rfu_2	Reserved for future use.	Currently not used.
rfu[RFU_COUNT]	Array of fields reserved for future use.	Specified values are in 10 millisecond increments. For example, a specified value of 100 is equivalent to 1 second. Possible values are: 0 = Default value for switch· 1 = Default value for switch· 0 < n < 1 = Timer value in tens of milliseconds Note: Incorrect or unreasonable timer settings will result in undesirable effects to calls as well as the call control stack. Before you override the default values, you need to understand the timer meanings and their interdependencies.
T3xx (T302, T303, T304, T305, T306, T308, T309, T310, T312, T313, T318, T319, T322)	Defines the Layer 3 timer values. See Q.931 specification and corresponding switch specifications for exact definitions and default values for these timers. Not all timers are applicable to all of the switches.

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