AR# 9639

3.1i D_IP1 CORE Generator - Older COE files will not work with Distributed Memory and RAM-based Shift Register cores

Description

Keywords: coefficient file, distributed memory, RAM-based, shift register, initialization,

Urgency: Standard

General Description:
The COE file format for the 3.1i Distributed Memory and RAM-based Shift Register cores has changed. If you have an old .coe file from a previous version of these cores, it may not work with D_IP1 updated cores.

Note that the new COE file format is not covered in the 3.1i CORE Generator manual.

Solution

Specifying Memory Contents using a COE File:

The initial contents of the memory can be defined using a text file known as a Coefficient (COE) File. COE files must have a ".coe" extension.

The COE file consists of two parameters, similar to an XCO file, but the end of each line is determined with the use of a semi-colon. The two parameters are:

memory_initialization_radix:
The radix of the initialization value is specified here, with the choices being 2, 10, or 16.

memory_initialization_vector:
Each row of memory elements is defined with a binary, decimal or hexadecimal number whose equivalent binary value represents whether an individual memory element along the width of the row is set to a "1" or a "0". Each row of memory initialization is separated by a space, up to the depth of the memory.

An example COE file is shown below:

(This example .coe file is for RAM that is 4 bits x 11 bits deep. Use a semi-colon (;) to comment out a line.)

memory_initialization_radix = 16;
memory_initialization_vector = 23f4 721 11ff;
AR# 9639
Date 08/23/2002
Status Archive
Type General Article