The sole purpose of this repository is to test for the presence of and Read/Write speed of the on-board APS6404L PSRAM Chip on the Pimoroni Pico 2 Plus board.

This is attached to the RP2350 QSPI Interface along with the on-board Flash mempory, though utilises a separate Chip Select line (GPIO47)

Using these settings, and overclocking the Pimoroni Pico Plus 2 I was able to achieve the following 32-Bit Read / Write values for un-cached access:

32 bit: PSRAM write 8MB in 306734 us, 27348152 B/s (27.3 MBytes / Sec) 32 bit: PSRAM read 8MB in 340694 us, 24622118 B/s (24.6 MBytes / Sec)

This uses PSRAM initialisation routines originally developed by Sparkfun for their RP2350 range of boards, their code being published on GitHub in the following repository: https://github.com/sparkfun/sparkfun-pico/tree/main/sparkfun_pico

Under an MIT license included as follows:

The MIT License (MIT)

Copyright (c) 2024 SparkFun Electronics

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