Embedded Memory User Guide: Agilex™ 5 FPGAs and SoCs

ID 813901
Date 9/03/2024
Public
Document Table of Contents

2.4.4. ECC Read-During-Write Behavior

M20K blocks offer two options for handling read operations during write operations in mixed-port configurations (when read and write ports simultaneously access the same address):
  • Old Data Output (Selectable): In this mode, when a read operation occurs during a write operation, the data output from the memory block reflects the previously stored data (old data) at that address. The ECC status will also be a predictable value. This mode ensures data consistency for read operations even during concurrent writes.
  • Undetermined Output (Default): This is the default mode. This mode prioritizes write operations. When a read occurs during a write, the data output from the memory block and the ECC status become uncertain (represented as "X" in the user guide). This prioritizes write completion but might lead to unpredictable data for read operations during writes.