 Bowmar Instrument Corporation introduced the "Bowmar Brain", a four-function pocket calculator, in September 1971 and the $ 179 calculator sold over 500,000 copies in the first year. Bowmar then developed the "901B" calculator that was priced at $ 120. In September 1972, Texas Instruments (TI) introduced the TI-2500 portable four-function calculator that also sold for $ 120. The 901B and the TI-2500 both used the TI TMS0100 family of "calculator-on-a-chip" integrated circuit. TI was now directly competing with their IC customers. Other semiconductor companies such as National Semiconductor and Rockwell began selling calculators. Commodore Business Machines and other office equipment companies also got into the market. A frenzied price war started. By early 1974, Ed Roberts found he could purchase a calculator in a retail store for less than his cost of materials. The larger companies could sell below cost to win market share. Bowmar lost $ 20 million in 1974 and filed for bankruptcy. Commodore acquired their IC supplier, MOS Technology. Texas Instruments won the price war but their calculator division lost $ 16 million in 1975.
