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Appendix B

CDI Service Events

Introduction

: About Events

Events Ordered Alphabetically

Events Ordered Numerically

Introduction

The CDI Service uses the same event reporting mechanism as CT Access. The structure informs the application about which event occurred on which CTA context. This appendix is a summary of the events generated by the CDI service.

About Events

All events in the CT Access environment are represented by the generic CTA_EVENT data structure, shown below: typedef struct { DWORD id; /* Event code (and source service ID) */ CTAHD ctahd; /* CT Access context handle */ DWORD timestamp; /* Timestamp */ DWORD userid; /* User-supplied ID */ DWORD size; /* Size of buffer if buffer is not NULL */ /* otherwise, may contain event-specific data */ void *buffer; /* Buffer pointer */ DWORD value; /* Event status or event-specific data */ DWORD objHd; /* Service client side object handle */ } CTA_EVENT;
This structure, returned by ctaWaitEvent, informs the application which event occurred on which CTA context, and provides additional information specific to the event.
The event's prefix relates the event to a specific Natural MicroSystems library of functions. For example, the CTA prefix indicates CT Access; CDI indicates CDI service.
CDI service events are defined in cdidef.h.
The event structure contains the following fields:

Field

Description

id

An event code defined in the library header file. All CDI service events are prefixed with CDIEVN_ and are defined in cdidef.h.

ctahd

The CTA context handle (returned from ctaCreateContext).

timestamp

The time since the DSP was booted, in milliseconds (modulo 65536). The resolution for CX board events is 2 milliseconds. To provide a wider range, the timer alternates between even values (0, 2, 4, ...65534) and odd values (1, 3, 5, ...65535), every (approximately) 65 seconds.

userid

The user-supplied ID. This field is unaltered by CT Access and facilitates asynchronous programming. Its purpose is to correlate a CT Access context with an application object/CTA context when events occur.

value

This is an event-specific value. This field can hold a reason code or an error code.

size

The size (bytes) of the area pointed to by buffer. If the buffer is NULL. this field may be used to hold an event-specific value.

buffer

A pointer to data returned with the event. The field contains an application process address and the event's size field contains the actual size of the buffer.

objHd

Service client side object handle.
Refer to the CT Access Developer's Reference Manual for a detailed explanation of events, errors, and reason codes in CT Access.

Field	Description
id	An event code defined in the library header file. All CDI service events are prefixed with CDIEVN_ and are defined in `cdidef.h`.
ctahd	The CTA context handle (returned from ctaCreateContext).
timestamp	The time since the DSP was booted, in milliseconds (modulo 65536). The resolution for CX board events is 2 milliseconds. To provide a wider range, the timer alternates between even values (0, 2, 4, ...65534) and odd values (1, 3, 5, ...65535), every (approximately) 65 seconds.
userid	The user-supplied ID. This field is unaltered by CT Access and facilitates asynchronous programming. Its purpose is to correlate a CT Access context with an application object/CTA context when events occur.
value	This is an event-specific value. This field can hold a reason code or an error code.
size	The size (bytes) of the area pointed to by buffer. If the buffer is NULL. this field may be used to hold an event-specific value.
buffer	A pointer to data returned with the event. The field contains an application process address and the event's size field contains the actual size of the buffer.
objHd	Service client side object handle.

Events Ordered Alphabetically

The following table is an alphabetical listing of CDI events and their descriptions: Event Name Description CDIEVN_A_CHANGE_OFF The A bit was just reset. CDIEVN_A_CHANGE_ON The A bit was just set. CDIEVN_BOARD_STATUS_CHANGE The board's status has changed. Note: This event is only received by applications registered to received status change events (see Section 4.4). CDIEVN_CX_HEART_BEAT_BACK Communication with the DSP has been re-established. CDIEVN_CX_HEART_BEAT_LOST Communication with the DSP has been lost. CDIEVN_DTMF_ENDED The current DTMF ended. CDIEVN_DTMF_STARTED DTMF started. The ASCII representation of the key is in the value field. CDIEVN_FLASH_HOOK Station issued a flash-hook. CDIEVN_OFF_HOOK Station picked up. CDIEVN_ON_HOOK Station hung up. CDIEVN_TIMER_DONE An on-board timer has stopped. The event value field contains the reason. CDIEVN_TIMER_START An on-board timer has started. CDIEVN_TIMER_STOP An on-board timer has stopped. CDIEVN_TIMER_TICK An on-board timer is reporting a timer tick. CDIEVN_TONE_DONE A tone transmission is complete.

Event Name	Description
CDIEVN_A_CHANGE_OFF	The A bit was just reset.
CDIEVN_A_CHANGE_ON	The A bit was just set.
CDIEVN_BOARD_STATUS_CHANGE	The board's status has changed. Note: This event is only received by applications registered to received status change events (see Section 4.4).
CDIEVN_CX_HEART_BEAT_BACK	Communication with the DSP has been re-established.
CDIEVN_CX_HEART_BEAT_LOST	Communication with the DSP has been lost.
CDIEVN_DTMF_ENDED	The current DTMF ended.
CDIEVN_DTMF_STARTED	DTMF started. The ASCII representation of the key is in the value field.
CDIEVN_FLASH_HOOK	Station issued a flash-hook.
CDIEVN_OFF_HOOK	Station picked up.
CDIEVN_ON_HOOK	Station hung up.
CDIEVN_TIMER_DONE	An on-board timer has stopped. The event value field contains the reason.
CDIEVN_TIMER_START	An on-board timer has started.
CDIEVN_TIMER_STOP	An on-board timer has stopped.
CDIEVN_TIMER_TICK	An on-board timer is reporting a timer tick.
CDIEVN_TONE_DONE	A tone transmission is complete.

Events Ordered Numerically

The following table is a list of events in numerical order: Hex Decimal Event Name 0x1F2001 2039809 CDIEVN_TONE_DONE 0x1F2002 2039810 CDIEVN_DTMF_STARTED 0x1F2003 2039811 CDIEVN_DTMF_ENDED 0x1F2004 2039812 CDIEVN_ON_HOOK 0x1F2005 2039813 CDIEVN_OFF_HOOK 0x1F2006 2039814 CDIEVN_FLASH_HOOK 0x1F2007 2039815 CDIEVN_A_CHANGE_OFF 0x1F2008 2039816 CDIEVN_A_CHANGE_ON 0x1F2009 2039817 CDIEVN_BOARD_STATUS_CHANGE 0x1F200A 2039818 CDIEVN_TIMER_TICK 0x1F200B 2039819 CDIEVN_TIMER_DONE 0x1F200C 2039820 CDIEVN_CX_HEART_BEAT_LOST 0x1F200D 2039821 CDIEVN_CX_HEART_BEAT_BACK 0x1F200E 2039822 CDIEVN_TIMER_START

Hex	Decimal	Event Name
0x1F2001	2039809	CDIEVN_TONE_DONE
0x1F2002	2039810	CDIEVN_DTMF_STARTED
0x1F2003	2039811	CDIEVN_DTMF_ENDED
0x1F2004	2039812	CDIEVN_ON_HOOK
0x1F2005	2039813	CDIEVN_OFF_HOOK
0x1F2006	2039814	CDIEVN_FLASH_HOOK
0x1F2007	2039815	CDIEVN_A_CHANGE_OFF
0x1F2008	2039816	CDIEVN_A_CHANGE_ON
0x1F2009	2039817	CDIEVN_BOARD_STATUS_CHANGE
0x1F200A	2039818	CDIEVN_TIMER_TICK
0x1F200B	2039819	CDIEVN_TIMER_DONE
0x1F200C	2039820	CDIEVN_CX_HEART_BEAT_LOST
0x1F200D	2039821	CDIEVN_CX_HEART_BEAT_BACK
0x1F200E	2039822	CDIEVN_TIMER_START

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