Hello all! I tried with 5 kOhms pullup and I have SD card working in MMC in 4 bits and 20 MHz freq! Seems like the pullup value was the issue ...

Cheers!

Hi again everyone! I continued to think about my issue and made some searches about the value that pullup resistor should have. Please look at this approach and correct me if something is wrong here: One thing to consider is to make sure that, given a R value for pullup, the input current value in E...

Hello again everyone! I have inspected the SDIO using a digital oscilloscope, and well it seems OK for D0 to D3 signals, at least in terms of shape (squared signals between 0 to 3.3V). I could not get anything regarding the clock signal: does anyone know what is supposed to be as a shape & frequency...

ESP_LJH wrote: ↑

Mon Aug 01, 2022 9:01 am

Could you send layout again? I could not see it.

You should be able to see the layout at this URL: http://drive.google.com/uc?export=view& ... hYeLukFc8N

Maybe my SDIO tracks are too close from each other??

chegewara wrote: ↑

Mon Aug 01, 2022 6:07 am

Time to use oscilloscope?

Yes I am going to use my brand new Hantek 6022BL ... keep you posted!

Hello! Some news on SDIO / Micro SD Card & 4 bits. I have 2 ESP 32, one on a PCB (layout was posted at start) and another one on a breadboard. On the breadboard so far it did not work at all, but checking it today I realized that I had no pull-up on the CLK of the Micro SD peripheral; adding a 10K p...

Well yes I am using Slot 1 and on this version of ESP32 I have to use the one listed on the table, which I do. I did some tests today using a switch on GPIO12, so that it is floating at boot, then I connect it to D2 of the SD Card, and this produced no change at all : still not working in 4 bits mod...

Hello! Thank you for answering! Short answer is: no. Longer answer is: well I did some research upon your question. It appears that, following WROVER-IE datasheet (available here ), the effect of my pull-up on GPIO12 is to have MTDI at 1 at reset, thus selecting VDD_SDIO to 1.8V. Hoping I am on the ...

Hello all! I am trying since several weeks to get working a Micro SD card peripheral with a ESP32-DevKitCVIE. Here is the layout of my PCB, on the right is the peripheral with the pin names for SDIO: http://drive.google.com/uc?export=view&id=1VKbetnYpMp_yaAVXeEP9klhYeLukFc8N I checked everything and...

Hello again! I did some investigations, and at last I could narrow down the issue. First I got some additional information about the disconnected reason: added this line of code in the event_handler: wifi_event_sta_disconnected_t *event = (wifi_event_sta_disconnected_t *) event_data; and got reason ...