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Introduction to ICBs

Generic ICB Format

The table below shows the generic format for an ICB.

ICB Type |
ICB ID |
Data Length |
Data[0] |
: |

ICB Type

0x01 - Action

0x02 - Data

0x03 - Extended

ICB Subtype

The subtype defines the specific action the ICB performs, or the data it contains. The subtype values are defined in the ICB Subtype section of this chapter. In each API message that uses ICBs, the subtypes supported for that message are listed.

Important! Some Action ICB subtype values are used to indicate different ICBs, but they are unique within a particular message. For example, in the Inseize Control message, subtype 0x01 is the Report Call Processing Event ICB, while in the Outseize Control message, subtype 0x01 is the Scan For Wink N ICB.

Also, a specific ICB may have a different subtype value in different messages. For example, in the Inseize Control message, the Report Call Processing Event ICB is subtype 0x01, while in the Outseize Control message it is 0x04.

Make sure you use the proper ICB subtype value as defined in the specific API message. Data ICB subtypes are unique system-wide.

ICB Data Length

The length of the data to follow.

ICB Data

The data for each subtype is defined in the ICB Data section of this chapter, and in any API message which supports the subtype. Not all ICBs include data.

In each message, the data for each supported ICB is presented in the following format, if applicable:

ICB Data Length
ICB Data [0]
:

See Information Control Block.
Outgoing call setup during real-time call processing on a specific channel.
Momentary interruption in a single frequency tone indicating the distant switch is ready to receive the digits just dialed.