ESP32 Forum

Is there a schematic or reference design that shows the PICO D4 hooked to an SD card AND to an SRAM chip (ESP-PSRAM64H) AND it works!

Hi guys,
Any comments on this?
I'm also trying to do the same.
I have the SD card fully working with the PICO-D4, I was about to change to the standard chip rather than the SOP since the SPRAM was only available in 1.8V and that wouldn't work with the internal 3.3V flash, but now there is a 3.3V version of the SPRAM which I have received samples for from EspressIf, however I have no idea where to connect it to get all three working concurrently (PICO's Internal Flash, extrenal 3.3V SPRAM, and Micro SD 4-line mode).

Does anyone know how to connect pico to psram? Which pins are connected?
Thanks

Hi,

You may try the following connection:

PICO <----> PSRAM
SD1 <----> SIO0
SD0 <----> SIO2
CLK <----> SCLK
CMD <----> SIO3
IO17 <----> SIO1
SD2/SD3 <----> CS#

Hope it'd help. Let me know if you have further questions. Thanks.

One additional note, if using PSRAM with PICO-D4 make sure the PSRAM uses 3.3V not 1.8V levels. The recently released ESP-PSRAM64H uses 3.3V. The ESP-PSRAM32/ESP-PSRAM64 (without the H) are 1.8V only and not compatible with ESP32-PICO-D4.

Is safe to modify IDF like https://github.com/espressif/esp-idf/is ... -417991037?

I don't see a big problem, but I want to make sure is the correct solution

ESP_Lvxinyue wrote:Hi,

You may try the following connection:

PICO <----> PSRAM
SD1 <----> SIO0
SD0 <----> SIO2
CLK <----> SCLK
CMD <----> SIO3
IO17 <----> SIO1
SD2/SD3 <----> CS#

Hope it'd help. Let me know if you have further questions. Thanks.

Hi, can I just clarify, CS# is that tied to both SD2 and SD3? or either SD2 and SD3?

Thanks,

Seon
unexpectedmaker.com

Also, do we need a 10k pull-up on the CE/CS pin? I've seen reference to a pullup on other SPIRAM diagrams on the ESP32, so curious if we need it for the PICO + SPIRAM?

Thanks,
Seon
unexpectedmaker.com

Hi,

For your reference, CS# is tied to either SD2 or SD3, and a 10k pull-up is necessary. Thanks.

ESP_Lvxinyue wrote:Hi,

For your reference, CS# is tied to either SD2 or SD3, and a 10k pull-up is necessary. Thanks.

Thanks!

Seon
unexpectedmaker.com