Digilent Eclypse Z7 Hardware Reference Manual page 27

Figure 9.1: microSD slot signals
Both low speed and high speed cards are supported, the maximum clock frequency
being 50 MHz. A Class 4 card or better is recommended.
Refer to section 2.1 microSD Boot Mode for information on how to boot from a microSD
card that contains a Zynq Boot Image.
The microSD is also commonly used to store non-configuration data needed by the
application. If doing this from a bare-metal application, the microSD card can be freely
accessed using standalone libraries included with a Xilinx SDK BSP project. If doing this
from a Petalinux generated embedded Linux system, the microSD can be
mounted/accessed like a standard block device, typically with a device node named
/dev/mmcblk0. See the Petalinux and Xilinx SDK documentation for more information.
10. USB Micro-AB Device/Host/OTG Port
The Eclypse Z7 implements one of the two available PS USB OTG interfaces on the
Zynq device. A Microchip USB3320 USB 2.0 Transceiver Chip with an 8-bit ULPI
interface is used as the PHY. The PHY features a complete HS-USB Physical Front-
End supporting speeds of up to 480Mbs. The PHY is connected to MIO Bank 1/501,
which is powered at 1.8V. The usb0 peripheral is used on the PS, connected through
MIO[28-39]. The USB OTG interface can act as an host, embedded host, or a
peripheral device, through the USB Micro AB connector(J5). The USB mode is
controlled from software by manipulating the USB0 peripheral controller in the Zynq PS.