Technical data

Managing Peripheral Devices
8.4 Connecting Devices and Loading Device Drivers
To suppress autoconfiguration, and still configure HSCs and MSCP-
served devices on remote nodes, add the following lines to the end of
SYCONFIG.COM:
$ STARTUP$AUTOCONFIGURE_ALL == 0
$ @SYS$SYSTEM:STARTUP CONFIGURE
$ EXIT
These commands suppress autoconfiguration but still execute the
CONFIGURE phase of STARTUP.COM.
However, if you add the command @SYS$SYSTEM:STARTUP
CONFIGURE to SYCONFIG.COM, AUTOGEN will fail with the following
error:
%RUN-F-CREPRC, process creation failed
-SYSTEM-F-DUPLNAM, duplicate name
This error is caused because SYCONFIG.COM is invoked by
both STARTUP.COM and AUTOGEN. When AUTOGEN runs,
the CONFIGURE process already exists (it was started when
SYCONFIG.COM was executed by STARTUP.COM). When AUTOGEN
invokes SYCONFIG.COM, the command you added attempts to start a
second CONFIGURE process. This command fails, causing AUTOGEN to
fail.
8.5 Automatically Configuring Devices for OpenVMS Alpha
Systems
Autoconfiguration is the process of discovering the hardware devices on a
system and loading the appropriate device drivers. File-based autoconfiguration
is a feature that enables OpenVMS Alpha to automatically configure third-party
hardware devices.
Beginning with OpenVMS Alpha Version 7.1, device configuration tables are
constructed from ASCII text files on the OpenVMS Alpha operating system disk.
By adding simple descriptions of their devices in the appropriate ASCII text file,
third parties and end users can configure non-Compaq supported devices and load
user-written device drivers.
The following sections briefly explain device configuration and describe how to use
the new file-based autoconfiguration method to configure non-Compaq supported
devices.
8.5.1 Understanding Device Configuration
A device is configured on OpenVMS when system code is able to locate it on a bus,
give it a name, and load a device driver for it. When a device is autoconfigured,
all these steps happen without any user intervention.
OpenVMS discovers devices during the boot process in a bus-specific manner. The
discovery process includes storing data about detected devices in bus-specific data
structures. These data structures are later used to search configuration tables
of known devices. The configuration table provides the information necessary to
determine the driver name, the device name, and other parameters for loading
and connecting the appropriate driver.
Managing Peripheral Devices 8–11