SDHC SPI Send Command

[dario.sortino]

Hello.

I have a custom board featuring nRF5340. I placed a microSD card reader in my board connected to SPI. I followed the fatfs zephyr example, but I'm struggling in mounting the disk.

I can correctly see the block count, sector size and capacity of the microSD, but as soon as I try to run fs_mount(&mp), the board resets.

When debugging, I saw that the board resets as it tries to run the function sdhc_spi_send_cmd

I don't know where the problem can be, since as I said I can correctly see the capacity of the card (I'm using a Premium microSDHC 32gb card by Verbatim )

I already tried to format the card both with Windows10 and the program SDCardFormatter, but nothing changed.

My devicetree for the spi/sd device is 

&spi1 {
	compatible = "nordic,nrf-spim";
	status = "okay";
	cs-gpios = < &gpio0 7 GPIO_ACTIVE_LOW >;
	sck-pin = < 8 >;
	mosi-pin = < 9 >;
	miso-pin = < 10 >;
	sdhc0: sdhc@0 {
		compatible = "zephyr,sdhc-spi-slot";
		reg = <0>;
		status = "okay";
		label = "SDHC0";
		mmc {
			compatible = "zephyr,sdmmc-disk";
			status = "okay";
		};
		spi-max-frequency = <16000000>;
	};	
};

And my connector is the following

[dario.sortino]

Here you have a scope trace of the SPI pins (SD card not placed) when I call sdhc_request

I know that MISO is stale because there is no SD (I'll try get a scope trace also with the SD in), but how does the rest look?

[dario.sortino]

This is instead sdhc_request when the SD card is in the slot. I honestly have no idea of what's happening.

[dario.sortino]

Some investigation led me to understand where it arises the -134 error.

It happens when the system checks the sd card type (either SDIO or SDMMC). The function sd_test_sdio returns -134.

Inside of that, we try to send a sdhc command with opcode 5 and response type 85. 

This is the scope trace of that transaction is the following

[dario.sortino]

Same return error also trying with a SanDisk Ultra microSDXC 128Gb.

I don't think it's a problem of the SD I'm using, since as the original post says, I was able at least to retrieve the SD size

[Turbo J]

That is a correct response "illegal command + idle state" from an SD card to a CMD5. SD cards don't typically support CMD5.

I've seen cards that need a power cycle when they receive unsupported commands.