| 摘要 |
PURPOSE:To prevent destruction of the contents of a volatile memory in spite of the loading/unloading actions of a memory cartridge, by providing a pull-up resistance which gives an access preventing level to the chip-enable terminal of a RAM chip together with a capacitor circuit to keep a stable access preventing level. CONSTITUTION:When a RAM cartridge 11 is manually loaded or unloaded, sliding noises are produced at the contact of a connector 10. The a RAM chip 111 is set under an enable-state and receives an inadvertent access in case the voltage level of a terminal CE1 is unstable owing to the input of large sliding noises given to the terminal CE1 or in the worst case the voltage of the CE1 is lowered down to such a level that satisfies the logic '0'. Thus a capacitor 115 is set between the terminal CE1 and an earth level to absorb the comparatively large noises.
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