battery voltage detect [BD(n)]

The signals BD1 and BD2 generated by the memory card as an indication of the condition of the battery on the memory card. Both signals are kept asserted when the battery is in good condition. When BD2 is negated while BD1 is still asserted, the battery is in a warning condition and should be replaced, although data integrity on the card is still assured. If BD1 is negated with BD2 either asserted or negated, the battery is no longer serviceable and data is lost.

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