5.40 Read Manufacturer/Device ID (RMDID)

The Read Manufacturer/Device ID (RMDID) instruction is supported in SPI and is used to identify the manufacturer and device ID of the memory device. To execute this operation, the host drives CE# low and transmits the RMDID command (90H), followed by three bytes set to 000000H. The device then outputs data on the falling edge of the SCK signal. The device returns two bytes of identification data: manufacturer (20H) and device ID (18H).

The data output stream continues until the operation is terminated by a low-to-high transition on CE#. Refer to Figure 5-37 for the RMDID instruction sequence in SPI.