GENERAL DESCRIPTION
The HM25Q128A-PWof non-volatile flash memory device supports the standard Serial Peripheral Interface (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 protocols. This multiple width interface is called SPI Multi-I/O or MIO.

The SPI protocols use only 4 to 6 signals:
✦ Chip Select (CS#)
✦ Serial Clock (CLK)
✦ Serial Data
   - IO0 (DI)
   - IO1 (DO)
   - IO2 (WP#)
   - IO3 (HOLD# / RESET#)