Tests for RAMs
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rom1: asynchronous ROM
srom01: Read (initialized ROM).

sram01: Read+Write (at the same address).
sram02: Write+Read (at the same address, enable, variable).
sram03: Read+Write (at the same address, enable, signal and R appears after W).
dpram1: Read+Write (using signals, without enables)
dpram2: Read+Write (using a variable, without enables)
dpram3: Read+Write (like dpram2 but downto)