The PGM Editor
The Commands View

The Commands view in the  PGM Editor shows the actual program, listing the various commands in chronological order. To facilitate orientation within a program, control commands are in black, comments in green, and Triggers and If Constructs in blue.

 Tip:

Dionex recommends always editing programs in the associated Device view (see Control/The PGM Editor  The Device Views). The Device view is easy to use and ensures correct command syntax. Use the Commands view only if the desired parameters are unavailable in the Device view.

A control command starts with the time at which the command is executed. The time appears in Decimal Minutes, i.e., "2.500" means "2 minutes, 30 seconds". The actual program instruction, such as AcqOn/Off, appears after the time.

 Note:

You can integrate control commands into a program or perform them separately either from the Online toolbar or via the script buttons on the control panels.

If the program instruction requires parameter input, enter the parameter(s) next in the text line. Use a point (".") to separate the parameter from the instruction. If several parameters are required, specify them in the following lines. Each parameter is identified by its parameter name, followed by "=" and the parameter value. Example:

2.500 Pressure.LowerLimit = 10 

 Pressure.UpperLimit = 250

You may include any number of comment lines between the instruction lines. Start each comment line with a semicolon.

 Note:

If you want to edit your program later in the Device views, Dionex recommends entering all comments right at the beginning of the program. In some cases, Chromeleon cannot assign comments to the associated commands when re-sorting. Thus, it may happen that some comments appear at the wrong position after you have edited the program in the Device views.

 Tip:

By definition, the injection, i.e., the Inject command, is performed at retention time = 0. All preceding commands have negative times; all following instructions have positive times.

The advantage is that the PGM time corresponds to the retention time of data reduction, e.g., integration, and thus, avoids errors such as falsely interpreted gradient profiles. The times of the AcqOn and AcqOff commands similarly coincide with the time axis of the reduction method.

Select Command on the Control menu or press the F8 key to open a dialog box that assists you in editing the control commands. You can enter all instruction components (time, instruction, instrument, parameter, comment) separately. The system configuration determines which instructions and instruments are listed in the dialog box:

 Note: 

If the PGM File and the timebase are not connected correctly, the F8 box is not available and the program lines are displayed in gray.

The input procedure via the respective device icons or the F8 key prevents entering invalid command syntax. If Chromeleon finds a command with unknown or incorrect syntax, the corresponding line appears red.

• Press <F4> or <SHIFT> + <F4> to browse through the errors and correct any invalid input.

When you edit a program file in the PGM Editor, the editor checks the validity of the instructions, also. You only have to enter the commands and their parameters and Chromeleon takes care of the rest. This means that Chromeleon:

• Arranges the lines in chronological order. (Select Sort by Retention Time on the Control menu.)

• Checks whether the input is valid. (Select Check on the Control menu.) For example:

  - Does the file contain at least one Inject command?

  - Is the first Inject command at time 0.000?

  - Does the file contain at least one Acquisition On command after the first inject? (If it does not, a warning appears)

  - Is a Acquisition Off command present for each Acquisition On command? (This input is compulsory.)

  - Are total and partial flow rates set at the beginning of the file (required for clearly defined gradients)?

  - Are the execution times of preceding instructions considered in the start times of program instructions? (If they are not considered, the start times in the program file do not coincide with the actual start time.)

  - Is the final instruction an end command?

Before a program is started, Chromeleon performs a Ready Check to check the program for validity. In case of logical errors, for example, when Pressure.LowerLimit exceeds Pressure.UpperLimit, the program cannot start and a message appears, such as:

In case of errors, which may affect the course of the program without being critical, a warning appears. In this case, you can start the batch, nevertheless:

If you are familiar with the  Program Syntax, you can change or extend your program directly from the keyboard. After editing, save the PGM File by selecting Save on the File Menu.

For more information about how to create and/or edit a PGM File, refer to Control:

 The Control Program

 The Program Syntax

 The Program Wizard

For information about the different Control Commands, refer to:

 Creating a Program

 Practical Tips for Device Control (Overview)