A SOFTWARE FLAMEWORK TO CONTROL A NETWORK-CONNECTED EQUIPMENT AS A PSEUDO DEVICE
Miho Ishii, T. Fukui, Taizo Masuda, T. Ohata · 2003
Recently network-connected measurement instruments and controllers have increased. Today, Ethernet could be understood as a kind of a field bus for the front-end subsystems. The network-connected equipment uses the socket communication as a common software interface. The socket interface requires different handling from bus attached device access, that is, control application programmers have to understand the socket communication protocol in detail. It is inconvenient for them to develop the software efficiently. We developed a software framework, Device Masquerade, which handles a network-connected device as a pseudo device. The socket interface can be controlled through common equipment access libraries like bus-attached devices. The Device Masquerade consists of three parts; 1) API functions to access pseudo device, 2) a communication client software to access the server running on the remote equipment, 3) a pseudo device driver to interconnect between application programs linking the API library and the communication client. The pseudo device driver implements the exclusive access control. It is possible to replace the socket with other protocol. We applied the Device Masquerade for the installation of motor control units in the linac control system.