The Octal Serial Peripheral Interface (OSPI) module is a Serial Peripheral Interface (SPI) module which allows single, dual, quad or octal read and write access to external flash devices. This module has a memory mapped register interface, which provides a direct memory interface for accessing data from external flash devices, simplifying software requirements.

The OSPI module is used to transfer data, either in a memory mapped direct mode (for example a processor wishing to execute code directly from external flash memory), or in an indirect mode where the module is set-up to silently perform some requested operation, signaling its completion via interrupts or status registers. For indirect operations, data is transferred between system memory and external flash memory via an internal SRAM which is loaded for writes and unloaded for reads by a device controller at low latency system speeds. Interrupts or status registers are used to identify the specific times at which this SRAM should be accessed using user programmable configuration registers.

For more information, see Octal Serial Peripheral Interface (OSPI) section in Peripherals chapter in the device TRM.