embedded-sdmmc-rs: SPI init (microcontroller) stuck in TimeoutWaitNotBusy,

Looked at the init sequence and saw 0xFF issued before CMD0, this PR fixes the issue for me.

Thanks!

About this issue

Original URL
State: closed
Created 3 years ago
Comments: 15 (11 by maintainers)

Most upvoted comments

According to the error, that’s an unexpected R1 response to a CMD0. Looking at https://www.sdcard.org/downloads/pls/pdf/?p=Part1_Physical_Layer_Simplified_Specification_Ver9.00.jpg&f=Part1_Physical_Layer_Simplified_Specification_Ver9.00.pdf&e=EN_SS1_9 Section 7.3.2.1, the R1 response is:

Bit 7 - must be 0
Bit 6 - Parameter Error
Bit 5 - Address Error
Bit 4 - Erase Sequence Error
Bit 3 - COM CRC Error
Bit 2 - Illegal Command
Bit 1 - Erase Reset
Bit 0 - In Idle State

We want 0x01. If we get 0xFF, the card is busy and hasn’t responded yet. If we get anything else after sending CMD0 (GO_IDLE) I don’t think there’s anything we can do except try again.

thejpster on Jan 28, 2023

Yeah. The branch I shared I’ve been able to use pretty reliably the past few days. At least for the project I was using where the existing PR wasn’t working.

mdarrik on Nov 1, 2022