Write is Controlled by NWE (SMC.MODE.WRITE_MODE = 1):

The following figure shows the waveforms of a write operation with SMC_MODE.WRITE_MODE set . The data is put on the bus during the pulse and hold steps of the NWE signal. The internal data buffers are switched to Output mode after the NWE_SETUP time, and until the end of the write cycle, regardless of the programmed waveform on NCS.

Figure 1. SMC_MODE.WRITE_MODE = 1. Write Operation is Controlled by NWE