The first version was based on LSI chips with an Intel 8008 as peripheral controller (keyboard, monitor and printer), before adopting the Zilog Z80 as main processor. In late 1972, a Sacramento State University team led by Bill Pentz built the Sac State 8008 computer, able to handle thousands of patients' medical records. The Sac State 8008 was designed with the Intel 8008. It had a full set of hardware and software components: a disk operating system included in a series of programmable read-only memory chips (PROMs); 8 Kilobytes of RAM; IBM's Basic Assembly Language (BAL); a hard drive; a color display; a printer output; a 150 bit/s serial interface for connecting to a mainframe; and even the world's first microcomputer front panel. In early 1973, Sord Computer Corporation (now Toshiba Personal Computer System Corporation) completed the SMP80/08, which used the Intel 8008 microprocessor. The SMP80/08, however, did not have a commercial release. After the first general-purpose microprocessor, the Intel 8080, was announced in April 1974, Sord announced the SMP80/x, the first microcomputer to use the 8080, in May 1974. Virtually all early microcomputers were essentially boxes with lights and switches; one had to read and understand binary numbers and machine language to program and use them (the Datapoint 2200 was a striking exception, bearing a modern design based on a monitor, keyboard, and tape and disk drives). Of the early "box of switches"-type microcomputers, the MITS Altair 8800 (1975) was arguably the most famous. Most of these simple, early microcomputers were sold as electronic kits—bags full of loose components which the buyer had to solder together before the system could be used. The period from about 1971 to 1976 is sometimes called the first generation of microcomputers. Many companies such as DEC, National Semiconductor, Texas Instruments offered their microcomputers for use in terminal control, peripheral device interface control and industrial machine control. There were also machines for engineering development and hobbyist personal use. In 1975, the Processor Technology SOL-20 was designed, which consisted of one board which included all the parts of the computer system. The SOL-20 had built-in EPROM software which eliminated the need for rows of switches and lights. The MITS Altair just mentioned played an instrumental role in sparking significant hobbyist interest, which itself eventually led to the founding and success of many well-known personal computer hardware and software companies, such as Microsoft and Apple Computer.