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Okay so I know when I need to build a parallel design I can put them near each other and make a 4k*8 to expand the databus. But on this one I only need to use half of them and the databus length is larger than my total chips can reach. But I thought 2k*12 requires 24k b of data and i have 32k of space to store data. So there has to be a way to do so.

When I use a parallel design I can reach 4k*8 but it is not enough.

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    \$\begingroup\$ Not if you need single cycle access (unless it happens to be dual-port memory). \$\endgroup\$
    – user16324
    Oct 26, 2015 at 11:23
  • \$\begingroup\$ are there any restrictions on what additional chips can be used (other than extra RAM of course!) \$\endgroup\$
    – tcrosley
    Oct 26, 2015 at 11:27
  • \$\begingroup\$ You could easily with 3. \$\endgroup\$ Oct 26, 2015 at 12:33
  • \$\begingroup\$ I can only use this amount of chips. That is why i cannot just use a parallel design. And since there is no way to do it in one clock cycle either i will make another control unit to decode addresses and select chips or i will make a parallel design and ask for an extra chip for the project. Thank you all for your time \$\endgroup\$
    – koksalb
    Oct 26, 2015 at 13:45

1 Answer 1

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The only way to increase the apparent width of a physical memory is to wrap it in a sequential circuit that executes multiple cycles internally for each external read or write cycle. This requires a means of multiplexing the data during write cycles and demultiplexing it during read cycles.

For example, you could turn your 4k × 8 physical memory into a 2k × 16 virtual memory by storing each 16-bit word in two consecutive 8-bit locations in the physical memory. The physical memory would execute two read or write cycles internally for each external cycle.

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