Generic Device Driver
Functions, Commands, and Error Messages

Defining Functions ("Function/Definition")

To create a new function:

• Select the Functions element or an existing function in the definition tree.

• Click New.

This action creates a new function using the default settings. The dialog box for editing the function opens.

• Enter the name for the new function. Make sure that the name is unique within the device.

• Audit level indicates the filter level from which on this property is displayed in the Audit Trail.

Defining Serial Commands of Functions ("Function/Command sequence")

When a function is selected in Chromeleon, the device driver sends a command sequence to the instrument. Follow the procedure described for properties to define these command sequences (see  Defining Serial Commands ("Property/Command sequence")).

In the case of functions, format instructions of a command can contain variable references to properties and to function parameters.

Defining Parameters ("Parameter/Definition")

To extend a function by parameters:

• Select the Parameter element or an existing function parameter on the Definition tree structure.

• Click New.

This action creates a new parameter using the default settings. The dialog box for editing the parameter is opened. The dialog box corresponds to the one for defining properties (see  Defining Single Properties ("Property/Definition")).

Make sure that the name of the parameter is unique within the function. It is possible to assign the same name both, to parameters of different functions and properties and parameters. However, in the latter case it is not possible to specify a variable reference to the property, as this type of reference always refers to the parameter by the same name.

Defining Error Messages ("Error/Definition")

To extend the device driver by an error message:

• Select the Errors element or an existing error message on the Definition tree structure.

• Click New.

This action creates a new error message using the default settings. The dialog box for editing the message opens. It contains three fields:

• Error text: Enter the text to be written to the Audit Trail. Each error message must have its own text.

• Serial string: Enter the characters sent by the instrument if it needs to indicate an error. When Chromeleon receives this string of characters, the Generic Device Driver logs the specified error message in the Audit Trail.

• Error level: Enter the priority of the generated error.

As errors are defined on the driver level, they are valid for all devices of the driver. The error message is linked to the device that is assigned to the serial interface on which the matching command string was received.

Predefined Properties and Functions

Chromeleon expects drivers and devices to supply certain properties and functions. The type of properties and their names depend on the device type. An autosampler (inject device) must have the Inject function and the Position and Volume properties. There are also optional properties and functions that Chromeleon supports only if they actually exist.

The settings of these properties and functions are partly predefined and cannot be changed. For example, the type of the Volume property is set to Floating Point and the unit to µl. The Inject function cannot be extended by parameters.

When generating a new device, all predefined properties and functions are automatically generated using the default settings that only need to be adapted to the driver requirements. You can delete the optionally available predefined properties and functions.

For an overview, refer to  The Generic Device Driver.