The LANSCE accelerator is an 800 MeV linear accelerator delivering beams for more than fifty years. As it has aged, maintenance and upgrades to its control system software components have become challenging and often deferred due to operational and schedule constraints. As a result, we have a wide variety of new and old software, difficult to re-use, with a large staff burden. Data is stored in redundant sources, inconsistent formats, and outdated technology. Multiple tools exist for the same tasks. Some production software is updated without proper processes. We describe our approach to modernizing LANSCE control system software with proper development processes. We consider reduction of diversity, redundancies, data sources. Migration to modern technologies is also discussed. We explore the possibility of language standardization, and describe our database implementation and other future plans. Lifecycle management is also considered. This years-long effort will utilize a risk-based strategy to address the most urgent issues while also ensuring steady progress, ultimately resulting in a coherent and maintainable suite of control system software.

A new Machine Protection System (MPS) and the Beam Position Limits Detector (BPLD) system are being developed for APS Upgrade (APS-U) accelerator storage ring. The MPS/BPLD system consists of one main MPS and 20 local MPS/BPLD controllers distributed around the ring, each local controller is located on every odd double sector. Each LMPS handles one double sector. Each double sector can be equipped up to seven Libera BPM electronics units. Each Libera unit processes up to four BPMs at Turn-by-Turn (TbT) rate. The Beam Position Limits Detector (BPLD) provides two types of protections: BPLD-ID and BPLD-BM for insertion device (ID) front-end (FE) and bending magnet (BM) incident radiation protection respectively. We select bumps using orbit feedback in a machine simulation to test the position limits of the system consistent with accelerator physics requirements for stable beam. This paper introduces the high level software implementation of APS-U BPLD-ID and BPLD-BM validation.