| 摘要 |
PURPOSE:To prevent malfunction due to the attachment and the detachment of a memory unit by grounding the primary and the secondary terminals of a connector which connects with a computer system body and respective memory units through a pull-down resistance. CONSTITUTION:When a high-level signal is impressed to a CPU11 through an I/O15 by operating the attachment/detachment switch 19 of the main computer system frame 10, the primary and the secondary terminals of the tri-state buffer 31 of an electric attachment and detachment protecting device 30 are separated and the secondary terminal 31b has high impedance. Then, the primary terminal 32a of the connector 32 is held at the ground potential through pull- down resistances 34a, 34b.... Similarly, the secondary terminal 32b of the connector 32 on the side of a memory chip 22 is also held at the ground potnetial and any noise due to the disconnection of the chip 22 from the main frame 10 is not generated through the connector 32 substantially. The attachment of the chip 22 to the main frame 10 prevents similarly malfunction due to noise, etc., originating from the attachment and the detachment of the memory unit. |
