FPGA Central

Currently we use iMpact to create daisy-chain .bin file for our
motherboard populated with plug-in cards, each with its own XC3S500E.
The plug-in cards configuration can be changed on the field so the bin
image must also be regenerated for the new configuraion. We need to
build a new daisy chain .bin file inside our embedded system. I was
trying to understand the file structure but all the descriptions of the
bitstream structure I found in application notes don't correspond to
the files generated by iMpact.

Has anyone tried to build daisy-chain .bin file programmatically out
from single-device .bin files? Thanks.

[email protected] schrieb:

> Currently we use iMpact to create daisy-chain .bin file for our
> motherboard populated with plug-in cards, each with its own XC3S500E.
> The plug-in cards configuration can be changed on the field so the bin
> image must also be regenerated for the new configuraion. We need to
> build a new daisy chain .bin file inside our embedded system. I was
> trying to understand the file structure but all the descriptions of the
> bitstream structure I found in application notes don't correspond to
> the files generated by iMpact.
>
> Has anyone tried to build daisy-chain .bin file programmatically out
> from single-device .bin files? Thanks.

yes anyone has done this.

What impact does is 'merging' the slave .BIT inside the master bit by
inserting the slave .BIT as single stream that written to LOUT
register. Well at least that is how it work for serial configuration.

I have tried to configure multiply devices in chain without the LOUT
trick but with little luck, usually both master and slave release done,
but only one of them actually starts, eg GHIGH of the slave doesnt
assert.

using impact to insert the second bit inside the master bit makes the
second (slave) device also to start properly.

I bet you are (will be) facing the same problem.

inserting the slave streams into LOUT record isnt complicated but you
need to parse the .BIT files in order to write out the resulting single
binary image that you need.

Antti
http://antti-brain.com

Well, I understand I'll have to parse the file structure to be able to
rebuild it. This is what I've been doing for a couple of last days.
The problem is that Xilinx app. notes describes all the PACKETS used in
file while I still have a problem undestanding the file STRUCTURE, i.e.
why are those packets are being organized in the way they are.

[email protected] schrieb:

> Well, I understand I'll have to parse the file structure to be able to
> rebuild it. This is what I've been doing for a couple of last days.
> The problem is that Xilinx app. notes describes all the PACKETS used in
> file while I still have a problem undestanding the file STRUCTURE, i.e.
> why are those packets are being organized in the way they are.

I have a xilinx bitstream 'dump' utility that can be used to look what
impact has done.

the bitstream composition isnt complicated

Antti