Description
No, Stratix® V device MLAB blocks do not support the byte enable option in x16 depth mode.
Resolution
If you want to use the byte enable option on Stratix® V device MLAB blocks, set the address depth to be greater than 16.
The Quartus® II software will be updated in a future version to disallow you from enabling the byte enable option in Stratix® V device MLAB blocks using x16 depth mode.