 Many more machines offered user-programmable writable control stores as an option (including the HP 2100, DEC PDP-11/60 and Varian Data Machines V-70 series minicomputers).The Mentec M11 and Mentec M1 stored its microcode in SRAM chips, loaded on power-on through another CPU.The Data General Eclipse MV/8000 ("Eagle") had a SRAM writable control store, loaded on power-on through another CPU.