M-RAM Definition

A synchronous, true dual-port memory, with registered inputs and optionally registered outputs, available in supported device (Arria® series devices) families. The M-RAM ( mega RAM) is useful for applications where a large volume of data must be stored on the device. In supported device, except for Stratix® III devices, each block is a 4096 x 144 RAM block and contains 589,824 RAM bits, including parity bits. You can configure the M-RAM as true dual-port, dual-port, and single-port RAM, and FIFO buffers; however, the M-RAM cannot be configured upon initialization. The design cannot assume a 0 or a 1 value inside the RAM at the end of configuration, so the RAM bits at the end of configuration are X (don't care) bits.

The following table lists the configurable sizes for the M-RAM memory block:

Operation Mode

M-RAM Size


4096 x 144 8192 x 72 16384 x 36 32768 x 18 65536 x 9


Read x M / Write x N Read x 144 / Write x 144

M, N = 9, 18, 36, or 72

True dual-port

port A x M / port B x N

M, N = 9, 18, 36, or 72