This family of devices connect to a host system via a SPI. Traditional SPI single bit serial input and output (Single I/O or SIO) is supported as well as optional two bit (Dual I/O or DIO) and four bit (Quad I/O or QIO) serial commands. This multiple width interface is called SPI Multi-I/O or MIO. In addition, the FL-S family adds support for DDR read commands for SIO, DIO and QIO that transfer address and read data on both edges of the clock.The Eclipse architecture features a Page Programming Buffer that allows up to 128 words (256 bytes) or 256 words (512 bytes) to be programmed in one operation, resulting in faster effective programming and erase than prior generation SPI program or erase algorithms. Executing code directly from flash memory is often called Execute-In-Place or XIP. By using FL-S devices at the higher clock rates supported, with QIO or DDR-QIO commands, the instruction read transfer rate can match or exceed traditional parallel interface, asynchronous, NOR flash memories while reducing signal count dramatically.The S25FL128S and S25FL256S products offer high densities coupled with the flexibility and fast performance required by a variety of embedded applications. They are ideal for code shadowing, XIP and data storage.