Byte-Wide Write Enable – BWE_A, BWE_B

Byte-wide write enable (BWE) is a 9-bit bus. Depending on the BWE_MODE_A/B attribute setting, bit 9 (BWE[8]) might not be used. In PARITY_INTERLEAVED mode, only the eight least significant bits are used. A single parity bit for each of the DIN bytes 0–7 corresponds to and is written to the related parity bit in the MSB of the DIN bus. This mode supports a custom parity scheme. In PARITY_INDEPENDENT mode, the nine BWE bits correspond to a byte of the DIN bus. Table 1 details how the BWE_A/B bits can be used to enable the corresponding DIN bits during a write operation. The byte write enable inputs are ignored during a read operation.