General • Re: PSRAM for Pico2

What I was interested in was in finding out the read/write performance to PSRAM on something like the Pimoroni Pico Plus 2 or the SparkFun Pro Micro RP2350, and how you actually read and write to it in C - are there separate libraries, or is it supported in the Pico SDK?

Just a quick test on Pimoroni Pico Plus 2 with AP6404L,
raw access uncached (PSRAM is transparently mapped as RAM), 32 bit random writes:
280 MHz CPU / 2 = 140 MHz PSRAM ≈ 27 MB/s
320 MHz CPU / 2 = 160 MHz PSRAM ≈ 31 MB/s
same with more tuning ≈ 33 MB/s

That's excellent - many thanks for running those tests. Your 27 MB/s with a CPU speed of 280MHz compares directly with my 8.3 MB/s

So QSPI performance isn't quite 4 x SPI but it's better than 3 x SPI.

I now have a Pimoroni Pico plus 2 on order....

Statistics: Posted by Morphology — Wed Feb 19, 2025 12:58 pm

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