While top-end users still wait for those expected enhancements to the 3480 tape drive, IBM has moved to alleviate the problem of AS/400 users – of the B30 up, not the 9404-based B10 and B20 – by adding a high-speed feature to the 2440 A12 tape drive. The upgrade involves addition of hardware logic that enables the IBM 2440 A12 to operate at speeds of 75 or 147 inches per second. The higher rate is maintained automatically when sustained data is available from the host by using microcode controls and a 512Kb buffer at the 2440 Magnetic Tape Subsystem device level. The instantaneous data rate goes up to 918Kb per second at 6250 bpi and 235Kb per second at 1600bpi – double the previous rates. When sufficient data rate is not sustained by the host system, the tape subsystem will operate at 75 inches per second. The feature costs $6,000 – UKP4,532 – either as an upgrade or factory installed, and arrives next quarter. IBM promises a date for the high-speed feature for 9370 users of 2440s in first quarter 1990.
