Embedded Memory (RAM: 1-PORT, RAM: 2-PORT, ROM: 1-PORT, and ROM: 2-PORT) User Guide

ID 683240
Date 9/17/2021
Public
Document Table of Contents

3.11. Read Enable

Support for the read enable feature depends on the target device, memory block type, and the memory mode you select.
Table 10.  Read-Enable Support in Various Device FamiliesThis table lists the memory configurations for various device families that support the read enable feature.
Memory Modes M9K, M144K, M10K, M20K MLAB
Single-port RAM Supported
Simple dual-port RAM Supported
True dual-port RAM Supported
Tri-port RAM Supported
Single-port ROM Supported
Dual-port ROM Supported

If you create the read-enable port and perform a write operation (with the read enable port deasserted), the data output port retains the previous values that are held during the most recent active read enable. If you activate the read enable during a write operation, or if you do not create a read-enable signal, the output port shows the new data being written, the old data at that address, or a “Don't Care” value when read-during-write occurs at the same address location.