This circuit is a very simple model of dynamic RAM, with a capacity of four bits. There is only one column, with four rows.
Select which bit you want with the two inputs labeled "row select". The output is on the right. To write a bit, specify the bit you want to write with the "data" input and then click the "write" input. This will charge (or discharge) the appropriate capacitor.
The capacitors will slowly drain over time, so each row must be refreshed periodically. To do this, select the row and click the "refresh" input.
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