Design of ConSys System Kernel - Device Layer
Design of the Device layer
There is two basic forms of devices. The standard for of a device is a device connecting to actual hardware. This kind of device maintains a address map of the hardware for use by the data servers. the Other kind of device is a virtual device. This kind of device does not connect directly to hardware, but maintains a virtual map of parameters. This kind of device is used for logical grouping of parameters.
There is some basic roles for the devices:
- A device is a single instance. Contrary to the data servers, devices exist only in one instance for all clients.
- A device is loaded on boot time, and remains active until the kernel terminates.
- Information on active devices is located in the registry.
- A device is the implementation of the parameters registered in the database.
The basic types of devices that has to be implemented is:
- The base class CDevice. This is the base class for all devices. It handles registering of data servers that want information. It also has a separate entry containing a status value, that data servers can access.
- A class for accessing G64's on ASTRID.
- A class for accessing G64's on CRYRING.
- A class for the monochromator on the ASTRID undulator.
- A class for the ASTRID undulator.
- The ConSys System kernel will be represented as a device. It will map the status of all devices managed by the kernel as parameters in this virtual device.
For a time table for these devices se 'Project parts'.
Last Modified 11 January 2019