Make sure you have installed the control software as described in Software Comissioning.
Using multiple USB-SD-Muxes on a singe host is considered a common use case.
Thus, it is a good practice to access a USB-SD-Mux via the
/dev/usb-sd-mux/id* symlinks created by the provided udev-rule.
The following examples are based on a USB-SD-Mux with the ID 000000000101.
If you have set up the
udev rule to grant access to the USB-SD-Mux control
interface to your current user, you should be able to use it as shown below.
Otherwise you may need to use the
To multiplex the Micro-SD-Card to the DUT
$ usbsdmux /dev/usb-sd-mux/id-000000000101 DUT
The card insertion detection signal on the DUT's SD card controller is not toggled, when you switch into DUT-mode on the USB-SD-Mux. Therefore, you either need to signal this to the DUT externally or simply power-cycle the DUT.
To multiplex the Micro-SD-Card to the host:
$ usbsdmux /dev/usb-sd-mux/id-000000000101 host
To disconnect the micro SD card from DUT and Host:
$ usbsdmux /dev/usb-sd-mux/id-000000000101 off
To get the current status of the USB-SD-Mux:
$ usbsdmux /dev/usb-sd-mux/id-000000000101 get off
The default state of USB-SD-Mux is off.
The block device of an USB-SD-Mux is symbolically linked as