Direct Access Self-Defining Parameter

The direct access self-defining parameter provides the ID for use in the destination/origin structured field in the direct access of the IBM auxiliary device.

This SDP is always required to accompany the base query reply.

Table 1. IBM Auxiliary Device Direct Access Self-Defining Parameter
Offset Length Content Meaning
0 1 byte X'04' Parameter length
1 1 byte X'01' Direct access ID
2–3 2 bytes DOID Destination/origin ID
The value in these bytes is used in the ID field of the destination/origin structured field to identify the auxiliary device as the destination or origin of the data that follows.