Meanwhile, IBM began to worry that it was losing control of the industry it had created. In 1987, IBM released the PS/2 line of computers, most of which included the MCA bus. MCA included numerous enhancements over the 16-bit AT bus, including bus mastering, burst mode, software-configurable resources, and 32-bit capabilities. However, in an effort to reassert its dominant role, IBM patented the bus and placed stringent licensing and royalty policies on its use. A few manufacturers did produce licensed MCA machines (most notably, NCR), but overall the industry balked at IBM's restrictions.
Meanwhile, IBM began to worry that it was losing control of the industry it had created. In 1987, IBM released the PS/:2 line of computers, most of which included the MCA bus. MCA included numerous enhancements over the 16-bit AT bus, including bus mastering, burst mode, softwar:e-configurable resources, and 32-bit capabilities. However, in an effort to reassert its dominant role, IBM patented the bus and placed stringent licensing and royalty policies on its use. A few manufacturers did produce license?d MCA machines (most notably, NCR), but overall the industry balked at IBM's restrictions.