User`s guide

2: DDCMP DLI Functions

DC 900-1343D 29

2.2.1 Initializing the DLI

The client application calls dlInit to initialize its interface to Freeway. This call speciﬁes

a DLI binary conﬁguration ﬁle, which is generated off-line from a text ﬁle (see

Appendix B for details of the conﬁguration process). The text ﬁle contains deﬁnitions

of the sessions that can be opened, as described in the following Section 2.2.2.

Since Raw operation does not perform automatic link conﬁguration, no protocol-spe-

ciﬁc link conﬁguration parameters are speciﬁed in the DDCMP DLI conﬁguration ﬁle.

2.2.2 DDCMP DLI Session Conﬁguration

The DLI text conﬁguration ﬁle consists of the following sections:

• A “main” section which speciﬁes the DLI conﬁguration for non-session-speciﬁc

operations.

• One or more additional sections, each specifying a protocol-speciﬁc session asso-

ciated with a particular Freeway serial communication link (port). Each link can

be conﬁgured independently of the other links.

The session parameters are described in the Freeway Data Link Interface Reference

Guide. Each session has an associated TSI connection name (the

transport parameter

in Figure 2–1) which you also must specify in your TSI conﬁguration ﬁle, though mul-

tiple sessions can use the same TSI connection.

For a Freeway server, Figure 2–1 is an example DLI conﬁguration ﬁle showing the

“main” section and two DDCMP sessions. You need to include only those session

parameters whose values differ from the defaults.

For DDCMP sessions, the required conﬁgurations which differ from the defaults are:

• alwaysQIO = “yes” • asyncIO = “yes”

• cfgLink = “no” • enable = “no”

• localAck = “no” • protocol = “raw”