TOSBAC-5100

This was a mid-size business processing computer announced by Tokyo Shibaura Electric in 1965. It employed a horizontal microcode system based on a diode matrix. Three TOSBAC-5100 models were developed , first the Model 10 and the Model 20, and then, in 1969, the model 30 which used LSI. The OS (called "COS") was developed in stages in response to progress in input/output devices: COS/MT for batch processing based on magnetic tape, and COS/DS for batch processing using a magnetic disk.