This was a mid-range machine in the HITAC M Series of general-purpose computers. At this time, many computer users faced severe problems with increasing system developing costs, and obtaining development personnel. In 1979, Hitachi announced the M-140H, 150H and 160H as new mid-size models in the M Series to respond to these user needs. Its features included: greatly improved cost-performance, Japan's first 600MB class disk drive equipped with two positioning mechanisms, interactive processing, and functional enhancements for greater automation and labor-saving.
| M-140H | M-150H | M-160H | |
|---|---|---|---|
| Main memory capacity | 0.5-4MB | 1-4MB | 2-6MB |
| Buffer memory capacity | - | - | 8KB |
| Channel throughput | 5MB/sec | 5.5MB/sec | 7MB/sec |
