User`s guide

38 DC 900-1516D
ICP2432 User’s Guide for OpenVMS Alpha (DLITE Interface)
3.3 DLITE Interface
The DLITE interface is described here in terms of enhanced capabilities, limitations and
caveats, the API itself, configuration files, and logging/tracing (see Section 3.3.4).
Within each context, necessary changes and any behavior differences are noted.
3.3.1 DLITE Limitations and Caveats
3.3.1.1 Raw Operation Only
DLITE supports only Raw operation. As with DLI, Raw operation means that the API
sends nothing to the ICPs except that which is provided by the application for transmis-
sion; therefore, the client application must handle all the following:
• Configuration of the ICP/Protocol
• ICP and protocol control data (using the DLI OptArgs structure accompanying
each
dlRead and dlWrite request)
• I/O details of the specific protocol
Raw operation especially impacts configuration of the ICP. Whereas Normal operation
performs ICP configuration for the application using information from the DLI config-
uration file, the application using Raw operation is totally responsible for configura-
tion. The DLI configuration file does not support “protocol” parameters (in fact, their
presence results in errors during configuration file processing because they are not
allowed in Raw operation).
3.3.1.2 No LocalAck Processing Support
Local acknowledgment (LocalAck) processing is not supported. When data is written to
an ICP, the user receives an acknowledgment that the ICP did in fact receive that data
(refer to your protocol-specific programmer’s guide for details). The Freeway DLI does
support a “LocalAck” capability that hides this from the application programmer (pre-