micropython / micropython/micropython

ESP32 SDMMC with pin reassignment

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needs-info port-esp32 proposed-close
Dominant language
C
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Description

I prefer SD_MMC(3 signal wires) than SPI methods(4 signal wires).
But, It seems to be pin assignment was fixed at ESP-IEF SDK here and, here

uSD | 1-bit Slot1 | SPI(native2,3/GPIO)
----+-------------+---------------------
 3  |   CMD(15)   | MOSI(13,23/any)
 5  |   CLK(14)   | SCK(14,18/any)
 7  |   D0(2)     | MISO(12,19/any)

I wish to avoid using strapping pins. I know workaround for GPIO12(burn efuse for VDD regs) only.
But I don't know how to workaround GPIO2 while I using SDMMC mode.
Any suggestions?

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First steps

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start with the ESP-IDF SDMMC overview and the referenced driver/include/driver/sdmmc_host.h definition around line 82. Determine whether SDMMC pin reassignment is supported for the ESP32 configuration described, including the GPIO2 strapping-pin concern. Done means documenting a supported workaround or confirming the limitation and its practical alternative.

Written by the indexing model from the issue text.

Assessment

Tech stack
c
Domain
embedded-iot
Issue type
Feature
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
30/100

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