CP/M 2.2 was also available. Under CP/M 2.2 the internal BASIC ROM was paged out for the CP/M ROM but this gave only 32 kB memory to CP/M. With the expansion module fitted the three 8 kB ROMs of the processor module were paged out to give the NewBrain one of the highest available TPA (Transient Program Area — memory left after the OS demands are satisfied) to CP/M. Grundy Business Systems released two 5.25" drive formats, 40 track 200 kB single sided and 80 track 800 kB double sided. Several independent dealers provided 40 track 400 kB double sided drive. In 1983 the Sony 3.5" became available and single and paired units were supplied to dealers in the NewBrain cream cases. The 3.5" 800 kB discs also got a more effective format allowing the files from 4x200 kB floppies to be stored on one 800 kB disc.