Minus 3: a general purpose data acquisition system at LBL's 88''-cyclotron and superhilac

MINUS 3 is a general, multi-tasked data acquisition package operating on the ModComp IV/25 computers at both the 88''-Cyclotron and SuperHILAC. It currently can acquire data via three different channels: interrupt; serial DMA link; and remote slave units for histogram type data. Two additional acquisition paths, CAMAC (with programmable differential branch drivers) and MODACS (for multiple CPU linkages and control) are scheduled to be added in the near future. The package operates in a prioritized, time-available mode which permits it to dynamically adapt to microscopic data rate structures due to beam characteristics at different accelerators. Special hardware has been added to the graphics system to provide enhanced high-speed interactive capability. The program framework is also designed as a parasitic environment in which users may, in parallel, attach their own specialized and independent code