UPGRADE YOUR BROWSER

We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

AR# 13127

4.1i PROMGen - Checksums change depending upon the fill value, even when a PROM is full

Description

Keywords: PROMGen, checksum, daisy chain

Urgency: Standard

General Description:
PROMGen reports checksums for each PROM in a chain. However, the checksum changes depending upon the fill value, even when the PROM is full.

When the PROM is full, all memory cells are programmed, so the fill value should have no effect on the checksum.

Solution

This issue is due to a problem with PROMGen that is fixed in software version 5.1i.

NOTE:
-For a full PROM, PROMGen will calculate the correct checksum if the fill value is set for "0x00".
-For a PROM that is not full, PROMGen will calculate the correct checksum if the fill value is set for "0xFF".

Given this information, you can work around the problem by running PROMGen twice:

1. Set the fill value to "0x00" and run PROMGen. The resulting checksum should be used for all PROMs that are full (generally all but the last PROM in a PROM chain).

2. Set the fill value to "0xFF" and rerun PROMGen. The resulting checksum should be used for any PROMs that are not full (generally only the last PROM in a PROM chain).
AR# 13127
Date Created 08/29/2007
Last Updated 09/30/2005
Status Archive
Type ??????