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AR# 40740

MIG Spartan-6 MCB - Read Latency


This section of the MIG Design Assistant focuses on Read Latency of the Spartan-6 MCB designs. See below to find information related to your specific question.

Note: This Answer Record is a part of the Xilinx MIG Solution Center (Xilinx Answer 34243). The Xilinx MIG Solution Center is available to address all questions related to MIG. Whether you are starting a new design with MIG or troubleshooting a problem, use the MIG Solution Center to guide you to the right information.


Read latency is measured from the point where the read command is accepted by the User Interface and when the Read data is received. Below are several parameters that can vary the Read Latency:

The number of commands already in the pipeline before the read command is issued

Whether an ACTIVATE command needs to be issued to open the new bank/row

Whether a PRECHARGE command needs to be issued to close a previously opened Bank

Specific timing parameters for the memory, such as, TRAS and TRCD with the bus clock frequency

Commands can be interrupted, and banks/rows can forcibly be closed when the periodic AUTO REFRESH command is issued

CAS latency

For specific values in clock cycles and a further description of Read Latency for Spartan-6 MCB designs, please see the Spartan-6 FPGA Memory Controller User Guide(UG388)section, "Read Latency."

Linked Answer Records

Associated Answer Records

Answer Number Answer Title Version Found Version Resolved
40156 MIG Spartan-6 MCB - Performance N/A N/A
AR# 40740
Date Created 08/22/2011
Last Updated 12/15/2012
Status Active
Type General Article
  • Spartan-6 LX
  • Spartan-6 LXT
  • MIG