I certainly can't imagine a situation where I would use a 2TB+ SD card in Pico ![:D]( "Very Happy")
Incidentally, the FatFs library also supports ExFat as an option, so this should not be a problem. However, the user-added SD card driver part must handle the SD card type appropriately. For example, older SD cards (<2GB) are addressed in bytes, while SDHC cards (<32GB) and SDXC cards (<2TB) need to be switched to 512-byte units. In addition, to handle the entire area on SD cards of 4 GB or more, the address needs to be managed in a variable type of 32 bits or more.
I do not think that SPI Mode support for SD cards (except for SDUC cards) is a problem. Instead, I think that the SD card driver software and the user application software could be a problem if the software is handling the SD card differences correctly.
I was looking at what I could get my hands on from the Simplified version SD Memory Card Specifications Physical layer specification Version 1.01 (April 2001!) in order, and the changes in description are a bit fun.
Incidentally, the FatFs library also supports ExFat as an option, so this should not be a problem. However, the user-added SD card driver part must handle the SD card type appropriately. For example, older SD cards (<2GB) are addressed in bytes, while SDHC cards (<32GB) and SDXC cards (<2TB) need to be switched to 512-byte units. In addition, to handle the entire area on SD cards of 4 GB or more, the address needs to be managed in a variable type of 32 bits or more.
I do not think that SPI Mode support for SD cards (except for SDUC cards) is a problem. Instead, I think that the SD card driver software and the user application software could be a problem if the software is handling the SD card differences correctly.
I was looking at what I could get my hands on from the Simplified version SD Memory Card Specifications Physical layer specification Version 1.01 (April 2001!) in order, and the changes in description are a bit fun.
The SPI compatible communication mode of the SD Memory Card is designed to communicate with a SPI channel, commonly found in various microcontrollers in market.
(Version 1.01, April 15 ,2001)
The SPI mode consists of a secondary communication protocol that is offered by Flash-based SD Memory Cards. This mode is a subset of the SD Memory Card protocol, designed to communicate with a SPI channel, found in some microcontrollers.
(Version 9.10, December 1, 2023 )
Statistics: Posted by 0yama — Wed Jul 10, 2024 1:37 pm