Re: 18F46k40 MSSP SPI Modes and SD-cards
OK. This is an existing design. I have two identical boards with the same FW, but prototyping this on existing boards is difficult, so I am breadboarding up just the processor, buffer and SD-socket to be able to test properly.
What I saw was really weird, ie comparing the board with the resistive divider/fet and the one with TXB0104. When you init the SD card, you keep CS low and feed in 74 or more clock pulses. At that point the SD card should output data to show it is there, but the TXB0104 variant does not. I tried different SD cards and checked all other signals...
I will post back when I have the breadboard circuit up and can test further.