To cater to the variety of lab environments, BLACS supports custom user code (that is not covered by a device implementation) in the form of plugins. Plugins allow custom graphical interfaces to be created through the addition of menu items, notifications, preferences editable through a common preferences panel, and custom tabs that sit alongside device tabs. Plugins are also provided access to a variety of internal BLACS objects, such as the shot queue, and can register callback functions to be run when certain events happen (such as a shot completing). This provides a powerful basis for customising the behaviour of BLACS in a way that is both modular and maintainable, providing a way to include optional conflicting features without needing to resolve the incompatibility. Plugins can be easily shared between groups, allowing for a diverse variety of control system interfaces that are all built on a common platform. We have developed several plugins at Monash, which are detailed in the following sections, and demonstrate the broad applicability of the plugin system.
The API refrence for the standard plugins is here
The connection table plugin¶
This plugin is included in the default install of BLACS, and provides a clean interface to manage the lab connection table that BLACS uses to automatically generate the device tabs and their graphical interfaces. The plugin inserts a menu item that provides shortcuts for:
editing the connection table Python file,
initiating the recompilation of the connection table, and
editing the preferences that control the behaviour of the plugin.
The preferences panel allows you to configure a list of hdf5 files containing runmanager globals to use during the compilation of the connection table (commonly used as unit conversion parameters), as well as a list of unit conversion Python files, to watch for any changes. At startup, the plugin launches a background thread that monitors changes to these files, as well as the connection table Python file and compiled connection table hdf5 file. If any modifications are detected, a notification is shown at the top of BLACS informing that the lab connection table should be recompiled. If recompilation is chosen by the user, the plugin manages the recompilation of the connection table using the runmanager API and output from this process is displayed in a window. Once recompilation is successful, the plugin relaunches BLACS so that the new connection table is loaded. This ensures that BLACS is using the same knowledge of the experiment apparatus as any future shots will when they are created by runmanager (assuming they share the globals files used).