Answers Database

xc4000EX/XL: Asynchronous Peripheral Configuration from MCS file causes INIT to go low.


Record #2059

Product Family:  Hardware

Product Line:  4000EX

Problem Title:
xc4000EX/XL: Asynchronous Peripheral Configuration from MCS file causes
INIT to go low.



Problem Description:
Keywords: 4000ex, 4000xl, asynchronous, peripheral, configuration, apm, init, da
taframe, error

Urgency: Standard

General Description: When configuring an FPGA in the Asynchronous Peripheral
Mode (APM) by decoding an mcs format promfile with a microprocessor, INIT
drives Low.


Solution 1:

This can be caused by an unexpected indexing line in the middle of the file.
When decoding prom files for FPGA configuration, the prom addressing data
must be removed.  This consists of 8 ascii hexidecimal characters, preceeded
by a colon (:), on each line in the file, and an indexing line.  See example
below:

:020000020000FC
:10000000FF04C584F8DAFFFD5BBFF5BBBFFD5BBF36
:10001000F5BFBFD77AFDF6EFFEEEEFEEFE6FED7E99

The first line is an indexing line in the mcs format.  The addressing for
each index begins at 10000 Hex.  When 10FFF Hex is reached in the address
section, a new index is inserted.  See example below:

:10FFF000FFFFFD5DFFFFFFFFFFFFFF9FFFF99FFF7B
:020000021000EC
:10000000FFAFFFFAFFFFFFAFFFFAAFDFFAFFE27FBC

If an mcs file is created for more than 557056 configuration bits, then
multiple index lines will be used.  Not stripping these out will cause them
to be decoded and sent to the FPGA as configuration data, and thus will
cause a dataframe error which is flagged by driving INIT low.



End of Record #2059