RP2040 SD Card SPI Benchmark

RE: RP2040 SD Card SPI Benchmark

LeScherd — Sun, 20 Mar 2022 16:08:03 GMT

Hi,
I ran similar tests a few months ago using the MBed Arduino core, the MBed SDFat lbrary and the standard SPI pins MISO 4, MOSI 3, SCK 2 and CS 5.
I set the SPI clock to 30MHz.
The results I got were significantly faster:
PicoPi 125MHz clock: W/R: 1450.54 KB/s / 1249.06 KB/s
PicoPi 250MHz clock: W/R: 1938.74 KB/s / 1774.31 KB/s
I didn't write down my results for the Philhower core... I must have run into issues.
I would be willing to try to set this experiment up again if you are interested.
I was never able to figure out a way to get SDIO working within the Arduino environment.
Thanks, Bill

RE: RP2040 SD Card SPI Benchmark

LeScherd — Sun, 20 Mar 2022 15:36:12 GMT

Hi,

A couple of months ago I ran a similar test using the Arduino Mbed core and SDFat library, using the standard MBed SPI pins: MISO 4, MOSI 3, SCK 2, CS 5.

I set the SPI clock rate at 30MHz.

I got the following data rates:

125MHz (PicoPi clock): W/R: 1450.54 KB/s / 1249.06 KB/s

250MHz clock: W/R: 1938.74 KB/s / 1774.31 KB/s

I would be willing to set up the experiment again to see if I get the same results. These results seem significantly faster than what you got... and I don't know why.

I never figured out how to implement SDIO in the Arduino environment, I would be very interested in hearing about that.

Bill

RE: RP2040 SD Card SPI Benchmark

dougw — Thu, 17 Mar 2022 21:47:33 GMT

Cool experiment. I wonder if it is possible to calculate.

140KB/s = 1,120kbits/s or 1.12 Mbits/s which is a long way from 50 Mbits/s. So how to calculate the overhead?

RE: RP2040 SD Card SPI Benchmark

DAB — Thu, 17 Mar 2022 19:18:42 GMT

Thank you for running the test.