System memory content editor

Note that you could also create two single port rams that are written to concurrently with your dp ram. Since the memory content editor can access these, you can do the same thing. The nice thing is your output will look more like memory contents, where signaltap will show it in a waveform format(unless there's a simple trick I don't know about). For example, if you're memory is 4K deep and your signaltap is, say 8K deep, it is unlikely that you'll capture at a time when all 4K locations have been written to over 8K cycles, so you won't actually see everything in there. Shadowing your ram with single-port in-system content memory editors will resolve that.

As you see, there can be a decent amount of engineering that goes into debugging, although it's almost always worth the investment. (One other thing I can think of is that the shadow single-port RAMs wouldn't actually feed anything, so they might get synthesized out. I doubt this will happen since turning on the In-System Content Editor adds logic to these memories that takes their output to the JTAG circuitry, but will leave that experiment up to the user....)