| 摘要 |
PURPOSE:To substitute one IC memory by another one differing in standard by using an IC memory adapter. CONSTITUTION:When 2K-bit PROM is substituted by 32K-bit PROM, data buses D0-D7, address buses A0-A7, and chip select CS are wired so that terminals of IC sockets 4 and 5 can correspond to each other. Although 2K PROM uses two power sources VCC of 5V and VDD of -9V, 32K PROm uses single power sources VCC of 5V, so voltage transformer 6 is used to wire them to terminals of IC sockets 4 and 5 by converting the power souces into the single power source. Because of a difference in memory capacity, address select switch 7 is fitted to the high-order four bits A8-A11 of address buses of 32k PROM for wiring to IC socket 5. |
