The iCE40 SPI Flash configuration interface supports a variety of SPI Flash memory vendors and product families. However, Lattice does not specifically test, qualify, or otherwise endorse any specific SPI Flash vendor or product family. The iCE40 SPI interface supports SPI PROMs that they meet the following requirements.
- The PROM must operate between 1.8V to 3.3V in order to trigger the iCE40 FPGA’s power-on reset circuit.
- The PROM must support the 0x0B Fast Read command, using a 24-bit start address and has 8 dummy bits before the PROM provides first data (see Figure 9).
- The PROM must have enough bits to program the iCE40 device.