The only issues I’m having with the SD Reader Mode is the U1_Connect signal and what I should be expecting from the read register command (J). The actual functionality is working great.
Prior to connecting the board to the computer but after successfully sending the initialize SD Reader Mode command (I D:) I expect the U1_Connect pin (pin 58) to go high. This does not occur, the U1_Connect pin stays low. The device status register reads $81 which is expected.
After connecting the board to the computer, I expect the U1_Connect pin to go low and the status register to read $C9. U1_Connect pin is low because it never changed to begin with and the status register reads $C1 (not expected).
I eject the device from my computer without unplugging the USB and nothing changes from the previous signal and register.
I then unplug the USB from the computer and the U1_Connect pin is still low and the status register is back to $81.
Is there a reason why the U1_Connect pin isn’t changing? I’m communicating in SPI mode so I’m using pin 58 as the U1_Connect pin. Also, shouldn’t I expect bit 3 (U1 mounted/unmounted) on the status register to toggle?
Thanks for the help.