User`s guide

3: Programming Using the DLITE Embedded Interface
DC 900-1516D 37
Instead, the embedded application using DLITE communicates directly with the
OpenVMS ICP2432 driver (through the VMS interface), which accesses the locally
attached ICP. This interface is shown in Figure3–2. In this environment no Freeway-
type communications take place; it is designed specifically for the embedded system.
3.2.2 Embedded Interface Objectives
The DLITE interface was designed as a streamlined interface to the ICP2432. It supports
only Raw operation protocols, which means that the application is responsible for all
communications with the ICP. DLITE supports only non-blocking I/O.
DLITE was designed to maximize portability between existing applications. The objec-
tive was an interface that would require “no changes” when porting from a Freeway
environment to an embedded environment. While this objective has been met (for Raw
operation using non-blocking I/O), there are differences between these environments,
as well as differences in system behavior. These differences are addressed in the follow-
ing sections.
Figure 3–2: DLITE Interface in an Embedded ICP2432 Environment
DLITE
Client
Application
dlicfg
DLITE Text
Configuration
File
DLITE Binary
Configuration File
DLI
Configuration
Preprocessor
(off-line)
VMS
Interface
ICP0
ICP1
ICP2
ICP3
PCI
Driver
WAN
Protocols
3515
PCIbus
VMS