| 摘要 |
<p>PURPOSE:To miniaturize a single chip microcomputer-mounted substrate and to omit the pins of an IC package without requiring any address decoder for chip selection signal generation and any dedicated output terminal for a chip selection signal for selecting an external memory chip from a single chip microcomputer. CONSTITUTION:An address decode circuit 8 is built in a single chip microcomputer 1 and generates a chip selection signal 9 from an address signal 7 for generating the chip selection signal of the external memory chip, and a switching circuit 11 selectively outputs an address signal 10 for specifying an access address inside the external memory chip and the chip selection signal 9 from an address/chip selection terminal 12 while switching the outputs of the chip selection signal 9 and the address signal 10.</p> |
