Hello!
I'm using an extern micro SD on T4. I've tried to find out if i need to use pull-up/pull-down on the CS,MISO,MOSI and SCLK , currently I'm using pullup ( to 3V3) resistor on MISO only. Should i use any other pull-up or pull-down on the other pins?
Since the T4 digital pins are 3.3V, you don't need a tristate buffer in the MISO, MOSI and SCLK pins, unless you wanted to use it for another device that's 5V.
I believe your MISO pin should float halfway between 3.3V and GND when not in use, according to the guide.
The reason is actually the placement of those pins, I'm a new beginner in this field! I thought it would be easier to don't use the SD pins since it i use SPI to communicate with SD.