Applications of asynchronous slow devices control system based on EPICS

For the fact that most of the front-end devices are slow devices with communication port in the control system of Linear Induction Accelerator (LIA), this paper combines synchronous communication module Asyn with StreamDevice module to realize the distributed control of these devices based on the EPICS architecture. The multi-parameter input and output methods are proposed based on SCPI and non-SCPI commands. The command format supported by domestic devices is not SCPI, and it is usually needed to read or write multiple PVs in one I/O command, but the protocol in StreamDevice does not support. In this paper, Calcout record is used to combine several PVs in to a structured array to implement setting multiple PVs at one time, and waveform record is used to implement reading multiple PVs at one time.