3.2.6.1 QSPI Serial Flash

The SAMA5D27 provides one Quad Serial Peripheral Interface (QSPI).

A QSPI is a synchronous serial data link that provides communication with external devices in Master mode.

The QSPI can be used in SPI mode to interface with serial peripherals such as ADCs, DACs, LCD controllers, CAN controllers and sensors, or in Serial Memory mode to interface with serial Flash memories.

The QSPI allows the system to execute code directly from a serial Flash memory (XIP, or eXecute In Place, technology) without code shadowing to RAM. The serial Flash memory mapping is seen in the system as other memories (ROM, SRAM, DRAM, embedded Flash memory, etc.).

With the support of the Quad SPI protocol, the QSPI allows the system to use high-performance serial Flash memories which are small and inexpensive, instead of larger and more expensive parallel Flash memories.

The figure below illustrates a socket implementation for the QSPI Flash memory.